MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Advances in Microbial Physiology' source. Fri, 27 Jan 2012 23:58:37 +0100 http://www.medworm.com/index.php?rid=5454668&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22114840%26dopt%3DAbstract Authors: Lovley DR, Ueki T, Zhang T, Malvankar NS, Shrestha PM, Flanagan KA, Aklujkar M, Butler JE, Giloteaux L, Rotaru AE, Holmes DE, Franks AE, Orellana R, Risso C, Nevin KP Abstract Geobacter species specialize in making electrical contacts with extracellular electron acceptors and other organisms. This permits Geobacter species to fill important niches in a diversity of anaerobic environments. Geobacter species appear to be the primary agents for coupling the oxidation of organic compounds to the reduction of insoluble Fe(III) and Mn(IV) oxides in many soils and sediments, a process of global biogeochemical significance. Some Geobacter species can anaerobically oxidize aromatic hydrocarbons and play an important role in aromatic hydrocarbon removal from contaminated aquifers. T... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5454668 Tue, 29 Nov 2011 18:00:03 +0100 5454668 http://www.medworm.com/index.php?rid=5454667&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22114841%26dopt%3DAbstract Authors: Hallinan JS, James K, Wipat A Abstract Large amounts of detailed biological data have been generated over the past few decades. Much of these data is freely available in over 1000 online databases; an enticing, but frustrating resource for microbiologists interested in a systems-level view of the structure and function of microbial cells. The frustration engendered by the need to trawl manually through hundreds of databases in order to accumulate information about a gene, protein, pathway, or organism of interest can be alleviated by the use of computational data integration to generated network views of the system of interest. Biological networks can be constructed from a single type of data, such as protein-protein binding information, or from data generated by multiple ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5454667 Tue, 29 Nov 2011 18:00:03 +0100 5454667 http://www.medworm.com/index.php?rid=5454666&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22114842%26dopt%3DAbstract Authors: Bowman LA, McLean S, Poole RK, Fukuto JM Abstract Nitric oxide and related nitrogen species (reactive nitrogen species) now occupy a central position in contemporary medicine, physiology, biochemistry, and microbiology. In particular, NO plays important antimicrobial defenses in innate immunity but microbes have evolved intricate NO-sensing and defense mechanisms that are the subjects of a vast literature. Unfortunately, the burgeoning NO literature has not always been accompanied by an understanding of the intricacies and complexities of this radical and other reactive nitrogen species so that there exists confusion and vagueness about which one or more species exert the reported biological effects. The biological chemistry of NO and derived/related molecules is complex, ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5454666 Tue, 29 Nov 2011 18:00:03 +0100 5454666 http://www.medworm.com/index.php?rid=5049592&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21722790%26dopt%3DAbstract Authors: McEwan AG, Djoko KY, Chen NH, Couñago RL, Kidd SP, Potter AJ, Jennings MP Recognition of the diversity of transcriptional regulators of the MerR family has increased considerably over the last decade and it has been established that not all MerR-like regulators are involved in metal ion recognition. A new type of MerR-like regulator was identified in Neisseria gonorrhoeae that is distinct from metal-binding MerR proteins. This novel transcription factor, the Neisseria merR-like regulator (NmlR) is related to a large and diverse group of MerR-like regulators. A common feature of the majority of the genes encoding the nmlR-related genes is that they predicted to control the expression of adhC, which encodes a glutathione-dependent alcohol dehydrogenase. The function of the NmlR... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5049592 Fri, 22 Jul 2011 04:15:26 +0100 5049592 http://www.medworm.com/index.php?rid=5049591&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21722791%26dopt%3DAbstract Authors: Frederix M, Downie AJ Many bacteria use 'quorum sensing' (QS) as a mechanism to regulate gene induction in a population-dependent manner. In its simplest sense this involves the accumulation of a signaling metabolite during growth; the binding of this metabolite to a regulator or multiple regulators activates induction or repression of gene expression. However QS regulation is seldom this simple, because other inputs are usually involved. In this review we have focussed on how those other inputs influence QS regulation and as implied by the title, this often occurs by environmental or physiological effects regulating the expression or activity of the QS regulators. The rationale of this review is to briefly introduce the main QS signals used in Gram-negative bacteria and then ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5049591 Fri, 22 Jul 2011 04:15:26 +0100 5049591 http://www.medworm.com/index.php?rid=5049590&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21722792%26dopt%3DAbstract Authors: Frey AD, Shepherd M, Jokipii-Lukkari S, Häggman H, Kallio PT Extensive studies have revealed that large-scale, high-cell density bioreactor cultivations have significant impact on metabolic networks of oxygen-requiring production organisms. Oxygen transfer problems associated with fluid dynamics and inefficient mixing efficiencies result in oxygen gradients, which lead to reduced performance of the bioprocess, decreased product yields, and increased production costs. These problems can be partially alleviated by improving bioreactor configuration and setting, but significant improvements have been achieved by metabolic engineering methods, especially by heterologously expressing Vitreoscilla hemoglobin (VHb). Vast numbers of studies have been accumulating during the past 20 y... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5049590 Fri, 22 Jul 2011 04:15:26 +0100 5049590 http://www.medworm.com/index.php?rid=5049589&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21722793%26dopt%3DAbstract Authors: Glaeser J, Nuss AM, Berghoff BA, Klug G Singlet oxygen is the primary agent of photooxidative stress in microorganisms. In photosynthetic microorganisms, sensitized generation by pigments of the photosystems is the main source of singlet oxygen and, in nonphotosynthetic microorganisms, cellular cofactors such as flavins, rhodopsins, quinones, and porphyrins serve as photosensitizer. Singlet oxygen rapidly reacts with a wide range of cellular macromolecules including proteins, lipids, DNA, and RNA, and thereby further reactive substances including organic peroxides and sulfoxides are formed. Microorganisms that face high light intensities or exhibit potent photosensitizers have evolved specific mechanisms to prevent photooxidative stress. These mechanisms include the use of que... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5049589 Fri, 22 Jul 2011 04:15:26 +0100 5049589 http://www.medworm.com/index.php?rid=5000467&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21722794%26dopt%3DAbstract Authors: Osman D, Cavet JS Both the essentiality and toxicity of transition metals are exploited as part of mammalian immune defenses against bacterial infection. Salmonella serovars continue to cause serious medical and veterinary problems worldwide and detecting deficiency and excess of different metal ions (such as copper, iron, zinc, manganese, nickel, and cobalt) is fundamental to their virulence. This involves multiple DNA-binding metal-responsive transcription factors that discriminate between elements and trigger expression of genes that mediate appropriate responses to metal fluxes. This review focuses on the metal stresses encountered by Salmonella during infection and the roles of the different metal-sensing regulatory proteins and their target genes in adapting to these cha... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=5000467 Wed, 06 Jul 2011 19:00:08 +0100 5000467 http://www.medworm.com/index.php?rid=4184646&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21078440%26dopt%3DAbstract Authors: Schleper C, Nicol GW Nitrification is a microbially mediated process that plays a central role in the global cycling of nitrogen and is also of economic importance in agriculture and wastewater treatment. The first step in nitrification is performed by ammonia-oxidising microorganisms, which convert ammonia into nitrite ions. Ammonia-oxidising bacteria (AOB) have been known for more than 100 years. However, metagenomic studies and subsequent cultivation efforts have recently demonstrated that microorganisms of the domain archaea are also capable of performing this process. Astonishingly, members of this group of ammonia-oxidising archaea (AOA), which was overlooked for so long, are present in almost every environment on Earth and typically outnumber the known bacterial ammonia... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=4184646 Sat, 20 Nov 2010 06:50:03 +0100 4184646 http://www.medworm.com/index.php?rid=4184645&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21078441%26dopt%3DAbstract Authors: Farhana A, Guidry L, Srivastava A, Singh A, Hondalus MK, Steyn AJ Mycobacterium tuberculosis (Mtb) is a remarkably successful pathogen that is capable of persisting in host tissues for decades without causing disease. Years after initial infection, the bacilli may resume growth, the outcome of which is active tuberculosis (TB). In order to establish infection, resist host defences and re-emerge, Mtb must coordinate its metabolism with the in vivo environmental conditions and nutrient availability within the primary site of infection, the lung. Maintaining metabolic homeostasis for an intracellular pathogen such as Mtb requires a carefully orchestrated series of oxidation-reduction reactions, which, if unbalanced, generate oxidative or reductive stress. The importance of oxidat... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=4184645 Sat, 20 Nov 2010 06:50:03 +0100 4184645 http://www.medworm.com/index.php?rid=4184644&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21078442%26dopt%3DAbstract Authors: Elsholz AK, Gerth U, Hecker M CtsR is the global transcriptional regulator of the core protein quality networks in low GC, Gram+ bacteria. Balancing these networks during environmental stress is of considerable importance for moderate survival of the bacteria, and also for virulence of pathogenic species. Therefore, inactivation of the CtsR repressor is one of the major cellular responses for fast and efficient adaptation to different protein stress conditions. Historically, CtsR inactivation was mainly studied for the heat stress response, and recently it has been shown that CtsR is an intrinsic thermosensor. Moreover, it has been demonstrated that CtsR degradation is regulated by a two-step mechanism during heat stress, dependent on the arginine kinase activity of McsB. Inte... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=4184644 Sat, 20 Nov 2010 06:50:03 +0100 4184644 http://www.medworm.com/index.php?rid=2573394&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19573695%26dopt%3DAbstract We present diverse mechanisms of pH homeostasis including cell buffering, adaptations of membrane structure, active ion transport, and metabolic consumption of acids and bases. PMID: 19573695 [PubMed - as supplied by publisher] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=2573394 Mon, 06 Jul 2009 18:22:02 +0100 2573394 http://www.medworm.com/index.php?rid=2573393&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19573696%26dopt%3DAbstract Authors: Cook GM, Berney M, Gebhard S, Heinemann M, Cox RA, Danilchanka O, Niederweis M Mycobacterium tuberculosis is a prototrophic, metabolically flexible bacterium that has achieved a spread in the human population that is unmatched by any other bacterial pathogen. The success of M. tuberculosis as a pathogen can be attributed to its extraordinary stealth and capacity to adapt to environmental changes throughout the course of infection. These changes include: nutrient deprivation, hypoxia, various exogenous stress conditions and, in the case of the pathogenic species, the intraphagosomal environment. Knowledge of the physiology of M. tuberculosis during this process has been limited by the slow growth of the bacterium in the laboratory and other technical problems such as cell aggre... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=2573393 Mon, 06 Jul 2009 18:22:02 +0100 2573393 http://www.medworm.com/index.php?rid=2573392&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19573697%26dopt%3DAbstract Authors: Peck MW The ability to form botulinum neurotoxin is restricted to six phylogenetically and physiologically distinct bacteria (Clostridium botulinum Groups I-IV and some strains of C. baratii and C. butyricum). The botulinum neurotoxin is the most potent toxin known, with as little as 30-100ng potentially fatal, and is responsible for botulism, a severe neuroparalytic disease that affects humans, animals, and birds. In order to minimize the hazards presented by the botulinum neurotoxin-forming clostridia, it is necessary to extend understanding of the biology of these bacteria. Analyses of recently available genome sequences in conjunction with studies of bacterial physiology are beginning to reveal new and exciting information on the biology of these dangerous bacteria. At the... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=2573392 Mon, 06 Jul 2009 18:22:02 +0100 2573392 http://www.medworm.com/index.php?rid=1894708&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18929067%26dopt%3DAbstract Authors: Brown PJ, Hardy GG, Trimble MJ, Brun YV Caulobacter crescentus has become the predominant bacterial model system to study the regulation of cell-cycle progression. Stage-specific processes such as chromosome replication and segregation, and cell division are coordinated with the development of four polar structures: the flagellum, pili, stalk, and holdfast. The production, activation, localization, and proteolysis of specific regulatory proteins at precise times during the cell cycle culminate in the ability of the cell to produce two physiologically distinct daughter cells. We examine the recent advances that have enhanced our understanding of the mechanisms of temporal and spatial regulation that occur during cell-cycle progression. PMID: 18929067 [PubMed - in process] (... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=1894708 Wed, 22 Oct 2008 13:52:16 +0100 1894708 http://www.medworm.com/index.php?rid=1894707&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18929068%26dopt%3DAbstract We present here a genome-based survey of the distribution and phylogenies of genes involved in oxidation of sulfur compounds in these strains. It is evident from biochemical and genetic analyses that the dissimilatory sulfur metabolism of these organisms is very complex and incompletely understood. This metabolism is modular in the sense that individual steps in the metabolism may be performed by different enzymes in different organisms. Despite the distant evolutionary relationship between GSB and PSB, their photosynthetic nature and their dependency on oxidation of sulfur compounds resulted in similar ecological roles in the sulfur cycle as important anaerobic oxidizers of sulfur compounds. PMID: 18929068 [PubMed - in process] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=1894707 Wed, 22 Oct 2008 13:52:16 +0100 1894707 http://www.medworm.com/index.php?rid=1894706&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18929069%26dopt%3DAbstract Authors: Barrie Johnson D, Hallberg KB Acidophilic micro-organisms are those (mostly prokaryotes) that grow optimally at pH <3 (extreme acidophiles) or at pH 3-5 (moderate acidophiles). Although once considered to comprise relatively few species of bacteria and archaea, the biodiversity of extreme acidophiles is now recognized as being extensive, both in terms of their physiologies and phylogenetic affiliations. Chemolithotrophy (the ability to use inorganic chemicals as electron donors) is widespread among extreme acidophiles, as ferrous iron and sulfur represent two major available energy sources in many natural and man-made extremely acidic environments. Dissimilatory reduction of iron and sulfur (as a consequence of their use as electron acceptors in oxygen-limited and anoxic en... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=1894706 Wed, 22 Oct 2008 13:52:16 +0100 1894706 http://www.medworm.com/index.php?rid=1894705&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18929070%26dopt%3DAbstract Authors: Daran-Lapujade P, Daran JM, van Maris AJ, de Winde JH, Pronk JT Chemostat cultivation of micro-organisms offers unique opportunities for experimental manipulation of individual environmental parameters at a fixed, controllable specific growth rate. Chemostat cultivation was originally developed as a tool to study quantitative aspects of microbial growth and metabolism. Renewed interest in this cultivation method is stimulated by the availability of high-information-density techniques for systemic analysis of microbial cultures, which require high reproducibility and careful experimental design. Genome-wide analysis of transcript levels with DNA micro-arrays is currently the most commonly applied of these high-information-density analysis tools for microbial gene expression. Ba... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=1894705 Wed, 22 Oct 2008 13:52:16 +0100 1894705 http://www.medworm.com/index.php?rid=1894704&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18929071%26dopt%3DAbstract Authors: Lambert C, Hobley L, Chang CY, Fenton A, Capeness M, Sockett L Predatory Bdellovibrio bacteriovorus bacteria are remarkable in that they attach to, penetrate and digest other Gram-negative bacteria, living and replicating within them until all resources are exhausted, when they escape the prey ghost to invade fresh prey. Remarkable remodeling of both predator and prey cell occurs during this process to allow the Bdellovibrio to exploit the intracellular niche they have worked so hard to enter, keeping the prey "bdelloplast" intact until the end of predatory growth. If one views motile non-predatory bacteria in a light microscope, one is immediately struck by how rare it is for bacteria to collide. This highlights how the cell surface of Bdellovibrio must be specialized and ada... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=1894704 Wed, 22 Oct 2008 13:52:16 +0100 1894704 http://www.medworm.com/index.php?rid=814038&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17707143%26dopt%3DAbstract Authors: Zannoni D, Borsetti F, Harrison JJ, Turner RJ Microbial metabolism of inorganics has been the subject of interest since the 1970s when it was recognized that bacteria are involved in the transformation of metal compounds in the environment. This area of research is generally referred to as bioinorganic chemistry or microbial biogeochemistry. Here, we overview the way the chalcogen metalloids Se and Te interact with bacteria. As a topic of considerable interest for basic and applied research, bacterial processing of tellurium and selenium oxyanions has been reviewed a few times over the past 15 years. Oddly, this is the first time these compounds have been considered together and their similarities and differences highlighted. Another aspect touched on for the first time by thi... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=814038 Wed, 22 Aug 2007 01:08:05 +0100 814038 http://www.medworm.com/index.php?rid=814037&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17707144%26dopt%3DAbstract Authors: de Graaf AA, Venema K The importance of the human large intestine for nutrition, health, and disease, is becoming increasingly realized. There are numerous indications of a distinct role for the gut in such important issues as immune disorders and obesity-linked diseases. Research on this long-neglected organ, which is colonized by a myriad of bacteria, is a rapidly growing field that is currently providing fascinating new insights into the processes going on in the colon, and their relevance for the human host. This review aims to give an overview of studies dealing with the physiology of the intestinal microbiota as it functions within and in interaction with the host, with a special focus on approaches involving stable isotopes. We have included general aspects of gut micro... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=814037 Wed, 22 Aug 2007 01:08:05 +0100 814037 http://www.medworm.com/index.php?rid=814036&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17707145%26dopt%3DAbstract Authors: Ferenci T The chemostat was devised over 50 years ago and rapidly adopted for studies of bacterial physiology and mutation. Despite the long history and earlier analyses, the complexity of events in continuous cultures is only now beginning to be resolved. The application of techniques for following regulatory and mutational changes and the identification of mutated genes in chemostat populations has provided new insights into bacterial behaviour. Inoculation of bacteria into a chemostat culture results in a population competing for a limiting amount of a particular resource. Any utilizable carbon source or ion can be a limiting nutrient and bacteria respond to limitation through a regulated nutrient-specific hunger response. In addition to transcriptional responses to nutrien... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=814036 Wed, 22 Aug 2007 01:08:05 +0100 814036 http://www.medworm.com/index.php?rid=814035&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17707146%26dopt%3DAbstract Authors: Bird AJ In fungal cells, transcriptional regulatory mechanisms play a central role in both the homeostatic regulation of the essential metals iron, copper and zinc and in the detoxification of heavy metal ions such as cadmium. Fungi detect changes in metal ion levels using unique metallo-regulatory factors whose activity is responsive to the cellular metal ion status. New studies have revealed that these factors not only regulate the expression of genes required for metal ion acquisition, storage or detoxification but also globally remodel metabolism to conserve metal ions or protect against metal toxicity. This review focuses on the mechanisms metallo-regulators use to up- and down-regulate gene expression. PMID: 17707146 [PubMed - in process] (Source: Advances in Microbi... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=814035 Wed, 22 Aug 2007 01:08:05 +0100 814035 http://www.medworm.com/index.php?rid=394088&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17027370%26dopt%3DAbstract Authors: Williams HD, Zlosnik JE, Ryall B Pseudomonas aeruginosa is a gram-negative, rod-shaped bacterium that belongs to the gamma-proteobacteria. This clinically challenging, opportunistic pathogen occupies a wide range of niches from an almost ubiquitous environmental presence to causing infections in a wide range of animals and plants. P. aeruginosa is the single most important pathogen of the cystic fibrosis (CF) lung. It causes serious chronic infections following its colonisation of the dehydrated mucus of the CF lung, leading to it being the most important cause of morbidity and mortality in CF sufferers. The recent finding that steep O2 gradients exist across the mucus of the CF-lung indicates that P. aeruginosa will have to show metabolic adaptability to modify its energy met... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394088 Mon, 05 Feb 2007 19:48:06 +0100 394088 http://www.medworm.com/index.php?rid=394087&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17027371%26dopt%3DAbstract Authors: Atack JM, Kelly DJ Cytochrome-c peroxidases (CCPs) are a widespread family of enzymes that catalyse the conversion of hydrogen peroxide (H2O2) to water using haem co-factors. CCPs are found in both eukaryotes and prokaryotes, but the enzymes in each group use a distinct mechanism for catalysis. Eukaryotic CCPs contain a single b-type haem co-factor. Conventional bacterial CCPs (bCCPs) are periplasmic enzymes that contain two covalently bound c-type haems. However, we have identified a sub-group of bCCPs by phylogenetic analysis that contains three haem-binding motifs. Although the structure and mechanism of several bacterial di-haem CCPs has been studied in detail and is well understood, the physiological role of these enzymes is often much less clear, especially in comparison... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394087 Mon, 05 Feb 2007 19:48:06 +0100 394087 http://www.medworm.com/index.php?rid=394086&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17027372%26dopt%3DAbstract We describe here the paradigm of Z-type N2OR, whose characteristics have been studied in most detail in the genera Pseudomonas and Paracoccus. Sequenced bacterial genomes now provide an invaluable additional source of information. New strains harbouring nos genes and capability of N2O utilization are being uncovered. This reveals previously unknown relationships and allows pattern recognition and predictions. The core nos genes, nosZDFYL, share a common phylogeny. Most principal taxonomic lineages follow the same biochemical and genetic pattern and share the Z-type enzyme. A modified N2OR is found in Wolinella succinogenes, and circumstantial evidence also indicates for certain Archaea another type of N2OR. The current picture supports the view of evolution of N2O respiration prior to the ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394086 Mon, 05 Feb 2007 19:48:06 +0100 394086 http://www.medworm.com/index.php?rid=394085&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17027373%26dopt%3DAbstract Authors: Williams SB Cyanobacteria such as Synechococcus elongatus PCC 7942, Thermosynechococcus elongatus BP-1, and Synechocystis species strain PCC 6803 have an endogenous timing mechanism that can generate and maintain a 24 h (circadian) periodicity to global (whole genome) gene expression patterns. This rhythmicity extends to many other physiological functions, including chromosome compaction. These rhythmic patterns seem to reflect the periodicity of availability of the primary energy source for these photoautotrophic organisms, the Sun. Presumably, eons of environmentally derived rhythmicity--light/dark cycles--have simply been mechanistically incorporated into the regulatory networks of these cyanobacteria. Genetic and biochemical experimentation over the last 15 years has ident... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394085 Mon, 05 Feb 2007 19:48:06 +0100 394085 http://www.medworm.com/index.php?rid=394090&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17010696%26dopt%3DAbstract Authors: Kalnenieks U The ethanol-producing bacterium Zymomonas mobilis can serve as a model organism for the study of rapid catabolism and inefficient energy conversion in bacteria. Some basic aspects of its physiology still remain poorly understood. Here, the energy-spilling pathways during uncoupled growth, the structure and function of electron transport chain, and the possible reasons for the inefficient oxidative phosphorylation are analysed. Also, the interaction between ethanol synthesis and respiration is considered. The search for mechanisms of futile transmembrane proton cycling, as well as identification of respiratory electron transport complexes, like the energy-coupling NAD(P)H:quinone oxidoreductase and the cyanide-sensitive terminal oxidase(s), are outlined as the key ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394090 Sun, 01 Jan 2006 07:00:00 +0100 394090 http://www.medworm.com/index.php?rid=394089&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17010697%26dopt%3DAbstract Authors: Clarke SR, Foster SJ An important facet in the interaction between Staphylococcus aureus and its host is the ability of the bacterium to adhere to human extracellular matrix components and serum proteins. In order to colonise the host and disseminate, it uses a wide range of strategies, the molecular and genetic basis of which are multifactorial, with extensive functional overlap between adhesins. Here, we describe the current knowledge of the molecular features of the adhesive components of S. aureus, mechanisms of adhesion and the impact that these have on host-pathogen interaction. PMID: 17010697 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394089 Sun, 01 Jan 2006 07:00:00 +0100 394089 http://www.medworm.com/index.php?rid=394084&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17091562%26dopt%3DAbstract Authors: Böck A, King PW, Blokesch M, Posewitz MC Enzymes possessing the capacity to oxidize molecular hydrogen have developed convergently three class of enzymes leading to: [FeFe]-, [NiFe]-, and [FeS]-cluster-free hydrogenases. They differ in the composition and the structure of the active site metal centre and the sequence of the constituent structural polypeptides but they show one unifying feature, namely the existence of CN and/or CO ligands at the active site Fe. Recent developments in the analysis of the maturation of [FeFe]- and [NiFe]- hydrogenases have revealed a remarkably complex pattern of mostly novel biochemical reactions. Maturation of [FeFe]-hydrogenases requires a minimum of three auxiliary proteins, two of which belong to the class of Radical-SAM enzymes and other ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394084 Sun, 01 Jan 2006 07:00:00 +0100 394084 http://www.medworm.com/index.php?rid=394083&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D17091564%26dopt%3DAbstract This article also examines applications and future use of OP-degrading microbes and enzymes for bioremediation, treatment of OP poisoning, and as biosensors. PMID: 17091564 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394083 Sun, 01 Jan 2006 07:00:00 +0100 394083 http://www.medworm.com/index.php?rid=394096&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D16221577%26dopt%3DAbstract Authors: Chang DE, Conway T PMID: 16221577 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394096 Sat, 01 Jan 2005 07:00:00 +0100 394096 http://www.medworm.com/index.php?rid=394095&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D16221578%26dopt%3DAbstract Authors: Barras F, Loiseau L, Py B Owing to the versatile electronic properties of iron and sulfur, iron sulfur (Fe/S) clusters are perfectly suited for sensing changes in environmental conditions and regulating protein properties accordingly. Fe/S proteins have been recruited in a wide array of diverse biological processes, including electron transfer chains, metabolic pathways and gene regulatory circuits. Chemistry has revealed the great diversity of Fe/S clusters occurring in proteins. The question now is to understand how iron and sulfur come together to form Fe/S clusters and how these clusters are subsequently inserted into apoproteins. Iron, sulfide and reducing conditions were found to be sufficient for successful maturation of many apoproteins in vitro, opening the possibilit... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394095 Sat, 01 Jan 2005 07:00:00 +0100 394095 http://www.medworm.com/index.php?rid=394094&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D16221579%26dopt%3DAbstract Authors: Cronan JE, Zhao X, Jiang Y A series of genetic, biochemical, and physiological studies in Escherichia coli have elucidated the unusual pathway whereby lipoic acid is synthesized. Here we describe the results of these investigations as well as the functions of enzyme proteins that are modified by covalent attachment of lipoic acid and the enzymes that catalyze the modification reactions. Some aspects of the synthesis and attachment mechanisms have strong parallels in the pathways used in synthesis and attachment of biotin and these are compared and contrasted. Homologues of the lipoic acid metabolism proteins are found in all branches of life, save the Archea, and thus these findings seem to have wide biological relevance. PMID: 16221579 [PubMed - indexed for MEDLINE] (Sour... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394094 Sat, 01 Jan 2005 07:00:00 +0100 394094 http://www.medworm.com/index.php?rid=394093&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D16221580%26dopt%3DAbstract Authors: McCrindle SL, Kappler U, McEwan AG Over the last two decades, the biochemistry and genetics of dimethylsulfoxide (DMSO) and trimethylamine-N-oxide (TMAO) respiration has been characterised, particularly in Escherichia coli marine bacteria of the genus Shewanella and the purple phototrophic bacteria, Rhodobacter sphaeroides and R. capsulatus. All of the enzymes (or catalytic subunits) involved the final step in DMSO and TMAO respiration contain a pterin molybdenum cofactor and are members of the DMSO reductase family of molybdoenzymes. In E. coli, the dimethylsulfoxide reductase (DmsABC) can be purified from membranes as a complex, which exhibits quinol-DMSO oxidoreductase activity. The enzyme is anchored to the membrane via the DmsC subunit and its catalytic subunit DmsA is no... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394093 Sat, 01 Jan 2005 07:00:00 +0100 394093 http://www.medworm.com/index.php?rid=394092&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D16221581%26dopt%3DAbstract Authors: Hellemond JJ, Bakker BM, Tielens AG African trypanosomes are parasitic protozoa of the order of Kinetoplastida, which cause sleeping sickness and nagana. Trypanosomes are not only of scientific interest because of their clinical importance, but also because these protozoa contain several very unusual biological features, such as their special energy metabolism. The energy metabolism of Trypanosoma brucei differs significantly from that of its host, not only because it comprises distinct enzymes and metabolic pathways, but also because some of the glycolytic enzymes are localized in organelles called glycosomes. Furthermore, the energy metabolism changes drastically during the complex life cycle of this parasite. This review will focus on the recent advances made in understandi... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394092 Sat, 01 Jan 2005 07:00:00 +0100 394092 http://www.medworm.com/index.php?rid=394091&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D16221582%26dopt%3DAbstract Authors: Koch AL, Silver S The First Cell arose in the previously pre-biotic world with the coming together of several entities that gave a single vesicle the unique chance to carry out three essential and quite different life processes. These were: (a) to copy informational macromolecules, (b) to carry out specific catalytic functions, and (c) to couple energy from the environment into usable chemical forms. These would foster subsequent cellular evolution and metabolism. Each of these three essential processes probably originated and was lost many times prior to The First Cell, but only when these three occurred together was life jump-started and Darwinian evolution of organisms began. The replication of informational molecules that made only occasional mistakes allowed evolution to ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394091 Sat, 01 Jan 2005 07:00:00 +0100 394091 http://www.medworm.com/index.php?rid=394101&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D15518828%26dopt%3DAbstract Authors: Pócsi I, Prade RA, Penninckx MJ Glutathione (GSH; gamma-L-glutamyl-L-cysteinyl-glycine), a non-protein thiol with a very low redox potential (E'0 = 240 mV for thiol-disulfide exchange), is present in high concentration up to 10 mM in yeasts and filamentous fungi. GSH is concerned with basic cellular functions as well as the maintenance of mitochondrial structure, membrane integrity, and in cell differentiation and development. GSH plays key roles in the response to several stress situations in fungi. For example, GSH is an important antioxidant molecule, which reacts non-enzymatically with a series of reactive oxygen species. In addition, the response to oxidative stress also involves GSH biosynthesis enzymes, NADPH-dependent GSH-regenerating reductase, glutathione S-transfer... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394101 Thu, 01 Jan 2004 07:00:00 +0100 394101 http://www.medworm.com/index.php?rid=394100&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D15518829%26dopt%3DAbstract Authors: Saraiva LM, Vicente JB, Teixeira M The flavodiiron proteins (first named as A-type flavoproteins) constitute a large superfamily of enzymes, widespread among anaerobic and facultative anaerobic prokaryotes, from both the Archaea and Bacteria domains. Noticeably, genes encoding for homologous enzymes are also present in the genomes of some pathogenic and anaerobic amitochondriate protozoa. The fingerprint of this enzyme family is the conservation of a two-domain structural core, built by a metallo-beta-lactamase-like domain, at the N-terminal region, harbouring a non-heme diiron site, and a flavodoxin-like domain, containing one FMN moiety. These enzymes have a significant nitric oxide reductase activity, and there is increasing evidence that they are involved in microbial resi... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394100 Thu, 01 Jan 2004 07:00:00 +0100 394100 http://www.medworm.com/index.php?rid=394099&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D15518830%26dopt%3DAbstract Authors: Cheng Vollmer A, Van Dyk TK The delicate and dynamic balance of the physiological steady state and its maintenance is well characterized by studies of bacterial stress response. Through the use of genetic analysis, numerous stress regulons, their physiological regulators and their biochemical processes have been delineated. In particular, transcriptionally activated stress regulons are subjects of study and application. These regulons include those that respond to macromolecular damage and toxicity as well as to nutrient starvation. The convenience of reporter gene fusions has allowed the creation of biosensor strains, resulting from the fusion of stress-responsive promoters with a variety of reporter genes. Such cellular biosensors are being used for monitoring dynamic system... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394099 Thu, 01 Jan 2004 07:00:00 +0100 394099 http://www.medworm.com/index.php?rid=394098&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D15518831%26dopt%3DAbstract Authors: Dimroth P, Cook GM In certain strictly anaerobic bacteria, the energy for growth is derived entirely from a decarboxylation reaction. A prominent example is Propionigenium modestum, which converts the free energy of the decarboxylation of (S)-methylmalonyl-CoA to propionyl-CoA (DeltaG degrees =-20.6 kJ/mol) into an electrochemical Na(+) ion gradient across the membrane. This energy source is used as a driving force for ATP synthesis by a Na(+)-translocating F(1)F(0) ATP synthase. According to bioenergetic considerations, approximately four decarboxylation events are necessary to support the synthesis of one ATP. This unique feature of using Na(+) instead of H(+) as the coupling ion has made this ATP synthase the paradigm to study the ion pathway across the membrane and its rel... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394098 Thu, 01 Jan 2004 07:00:00 +0100 394098 http://www.medworm.com/index.php?rid=394097&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D15518832%26dopt%3DAbstract Authors: Lovley DR, Holmes DE, Nevin KP Dissimilatory Fe(III) and Mn(IV) reduction has an important influence on the geochemistry of modern environments, and Fe(III)-reducing microorganisms, most notably those in the Geobacteraceae family, can play an important role in the bioremediation of subsurface environments contaminated with organic or metal contaminants. Microorganisms with the capacity to conserve energy from Fe(III) and Mn(IV) reduction are phylogenetically dispersed throughout the Bacteria and Archaea. The ability to oxidize hydrogen with the reduction of Fe(III) is a highly conserved characteristic of hyperthermophilic microorganisms and one Fe(III)-reducing Archaea grows at the highest temperature yet recorded for any organism. Fe(III)- and Mn(IV)-reducing microorganisms h... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394097 Thu, 01 Jan 2004 07:00:00 +0100 394097 http://www.medworm.com/index.php?rid=394107&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D14560662%26dopt%3DAbstract Authors: Scanlan DJ During the twenty years or so since the discovery of tiny photosynthetic cells of the genus Synechococcus in marine oceanic systems, a tremendous expansion of interest has been seen in the literature pertaining to these organisms. The fact that they are ubiquitous and abundant in major oceanic regimes underlies their ecological importance as significant contributors to marine C fixation. Recent advances in the physiology and biochemistry of these organisms are presented here, focusing on strains of the MC-A and MC-B clusters; it is stressed that the data contained herein should be put into the context of the ecological niche occupied by particular genotypes in situ. This system is ripe for joining the often separate disciplines of molecular ecology and microbial phy... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394107 Wed, 01 Jan 2003 07:00:00 +0100 394107 http://www.medworm.com/index.php?rid=394106&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D14560663%26dopt%3DAbstract Authors: Mukamolova GV, Kaprelyants AS, Kell DB, Young M Microbial culturability can be ephemeral. Cells are not merely either dead or alive but can adopt physiological states in which they appear to be (transiently) non-culturable under conditions in which they are known normally to be able to grow and divide. The reacquisition of culturability from such states is referred to as resuscitation. We here develop the idea that this "transient non-culturability" is a consequence of a special survival strategy, and summarise the morphological, physiological and genetic evidence underpinning such behaviour and its adaptive significance. PMID: 14560663 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394106 Wed, 01 Jan 2003 07:00:00 +0100 394106 http://www.medworm.com/index.php?rid=394105&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D14560664%26dopt%3DAbstract Authors: Kelly SL, Lamb DC, Jackson CJ, Warrilow AG, Kelly DE The cytochrome P450 (CYP) superfamily of genes and proteins are well known for their involvement in pharmacology and toxicology, but also increasingly for their importance and diversity in microbes. The extent of diversity has only recently become apparent with the emergence of data from whole genome sequencing projects and the coming years will reveal even more information on the diversity in microbial eukaryotes. This review seeks to describe the historical development of these studies and to highlight the importance of the genes and proteins. CYPs are deeply involved in the development of strategies for deterrence and attraction as well as detoxification. As such, there is intense interest in pathways of secondary metabol... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394105 Wed, 01 Jan 2003 07:00:00 +0100 394105 http://www.medworm.com/index.php?rid=394104&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D14560665%26dopt%3DAbstract Authors: Berks BC, Palmer T, Sargent F The Tat (twin arginine translocation) protein transport system functions to export folded protein substrates across the bacterial cytoplasmic membrane and to insert certain integral membrane proteins into that membrane. It is entirely distinct from the Sec pathway. Here, we describe our current knowledge of the molecular features of the Tat transport system. In addition, we discuss the roles that the Tat pathway plays in the bacterial cell, paying particular attention to the involvement of the Tat pathway in the biogenesis of cofactor-containing proteins, in cell wall biosynthesis and in bacterial pathogenicity. PMID: 14560665 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394104 Wed, 01 Jan 2003 07:00:00 +0100 394104 http://www.medworm.com/index.php?rid=394103&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D14560666%26dopt%3DAbstract Authors: Wu G, Wainwright LM, Poole RK Globins are an ancient and diverse superfamily of proteins. The globins of microorganisms were relatively ignored for many decades after their discovery by Warburg in the 1930s and rediscovery by Keilin in the 1950s. The relatively recent focus on them has been fuelled by recognition of their structural diversity and fine-tuning to fulfill (probably) discrete functions but particularly by the finding that a major role of certain globins is in protection from the stresses caused by exposure to nitric oxide (NO)--itself a molecule that has attracted intense curiosity recently. At least three classes of microbial globin are recognised, all having features of the classical globin protein fold. The first class is typified by the myoglobin-like haemprot... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394103 Wed, 01 Jan 2003 07:00:00 +0100 394103 http://www.medworm.com/index.php?rid=394102&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D14753180%26dopt%3DAbstract Authors: PMID: 14753180 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394102 Wed, 01 Jan 2003 07:00:00 +0100 394102 http://www.medworm.com/index.php?rid=394114&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D12073651%26dopt%3DAbstract Authors: Schoolnik GK The DNA microarray, a surface that contains an ordered arrangement of each identified open reading frame of a sequenced genome, is the engine of functional genomics. Its output, the expression profile, provides a genome wide snap-shot of the transcriptome. Refined by array-specific statistical instruments and data-mined by clustering algorithms and metabolic pathway databases, the expression profile discloses, at the transcriptional level, how the microbe adapts to new conditions of growth--the regulatory networks that govern the adaptive response and the metabolic and biosynthetic pathways that effect the new phenotype. Adaptation to host microenvironments underlies the capacity of infectious agents to persist in and damage host tissues. While monitoring the whol... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394114 Tue, 01 Jan 2002 07:00:00 +0100 394114 http://www.medworm.com/index.php?rid=394113&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D12073652%26dopt%3DAbstract Authors: Imlay JA The orbital structure of molecular oxygen constrains it to accept electrons one at a time, and its unfavourable univalent reduction potential ensures that it can do so only with low-potential redox partners. In E. coli, this restriction prevents oxygen from oxidizing structural molecules. Instead, it primarily oxidizes reduced flavins, a reaction that is harmful only in that it generates superoxide and hydrogen peroxide as products. These species are stronger oxidants than is oxygen itself. They can oxidize dehydratase iron-sulphur clusters and sulphydryls, respectively, and thereby inactivate enzymes that are dependent upon these functional groups. Hydrogen peroxide also oxidizes free iron, generating hydroxyl radicals. Because hydroxyl radicals react with virtually ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394113 Tue, 01 Jan 2002 07:00:00 +0100 394113 http://www.medworm.com/index.php?rid=394112&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D12073653%26dopt%3DAbstract Authors: Prasad R, Panwar SL, Smriti In view of the increasing threat posed by fungal infections in immunocompromised patients and due to the non-availability of effective treatments, it has become imperative to find novel antifungals and vigorously search for new drug targets. Fungal pathogens acquire resistance to drugs (antifungals), a well-established phenomenon termed multidrug resistance (MDR), which hampers effective treatment strategies. The MDR phenomenon is spread throughout the evolutionary scale. Accordingly, a host of responsible genes have been identified in the genetically tractable budding yeast Saccharomyces cerevisiae, as well as in a pathogenic yeast Candida albicans. Studies so far suggest that, while antifungal resistance is the culmination of multiple factors, th... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394112 Tue, 01 Jan 2002 07:00:00 +0100 394112 http://www.medworm.com/index.php?rid=394111&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D12073654%26dopt%3DAbstract Authors: Gilbert P, Maira-Litran T, McBain AJ, Rickard AH, Whyte FW Microbial biofilms impinge upon all aspects of our lives. Whilst much of this impact is positive, there are many areas in which the presence and activities of biofilms are regarded as problematic and in need of control. It is in this respect that biofilms reveal their recalcitrance towards many of the long-established antibiotics, and industrial and medical treatment strategies. The nature of the resistance of biofilms, in spite of much research, remains an enigma. Whilst it is recognized that reaction--diffusion limitation properties of the biofilm matrix towards the majority of treatment agents will impede access, this cannot be the sole explanation of the observed resistance. Rather, it will delay the death of cells... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394111 Tue, 01 Jan 2002 07:00:00 +0100 394111 http://www.medworm.com/index.php?rid=394110&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D12073655%26dopt%3DAbstract Authors: O'Brian MR, Thöny-Meyer L Haems are involved in many cellular processes in prokaryotes and eukaryotes. The biosynthetic pathway leading to haem formation is, with few exceptions, well-conserved, and is controlled in accordance with cellular function. Here, we review the biosynthesis of haem and its regulation in prokaryotes. In addition, we focus on a modification of haem for cytochrome c biogenesis, a complex process that entails both transport between cellular compartments and a specific thioether linkage between the haem moiety and the apoprotein. Finally, a whole genome analysis from 63 prokaryotes indicates intriguing exceptions to the universality of the haem biosynthetic pathway and helps define new frontiers for future study. PMID: 12073655 [PubMed - indexed for M... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394110 Tue, 01 Jan 2002 07:00:00 +0100 394110 http://www.medworm.com/index.php?rid=394109&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D12073656%26dopt%3DAbstract Authors: Pomposiello PJ, Demple B Oxidation can damage all biological macromolecules, and the survival of a cell therefore depends on its ability to control the level of oxidants. Microbes possess an astonishing variety of antioxidant defences, ranging from small, oxidant-scavenging molecules to self-regulating, homeostatic gene networks. Most often these antioxidant defences are activated by exposure to specific classes of oxidants. Interestingly, the isolation of pleiotropic mutations that impair or exacerbate the expression of subsets of oxidant-responsive genes led to the identification of global regulators. In a few, well-characterized cases, these regulators can transduce oxidative damage into gene regulation. Recently, the application of genomic tools to study the antioxidant re... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394109 Tue, 01 Jan 2002 07:00:00 +0100 394109 http://www.medworm.com/index.php?rid=394108&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D12073657%26dopt%3DAbstract Authors: Helmann JD Bacterial sigma (sigma) factors are an essential component of RNA polymerase and determine promoter selectivity. The substitution of one sigma factor for another can redirect some or all of the RNA polymerase in a cell to activate the transcription of genes that would otherwise be silent. As a class, alternative sigma factors play key roles in coordinating gene transcription during various stress responses and during morphological development. The extracytoplasmic function (ECF) sigma factors are small regulatory proteins that are quite divergent in sequence relative to most other sigma factors. Many bacteria, particularly those with more complex genomes, contain multiple ECF sigma factors and these regulators often outnumber all other types of sigma factor combined... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394108 Tue, 01 Jan 2002 07:00:00 +0100 394108 http://www.medworm.com/index.php?rid=394126&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11407111%26dopt%3DAbstract Authors: Green J, Scott C, Guest JR The cAMP receptor protein (CRP; sometimes known as CAP, the catabolite gene activator protein) and the fumarate and nitrate reduction regulator (FNR) of Escherichia coli are founder members of an expanding superfamily of structurally related transcription factors. The archetypal CRP structural fold provides a very versatile mechanism for transducing environmental and metabolic signals to the transcription machinery. It allows different functional specificities at the sensory, DNA-recognition and RNA-polymerase-interaction levels to be 'mixed and matched' in order to create a diverse range of transcription factors tailored to respond to particular physiological conditions. This versatility is clearly illustrated by comparing the properties of the CRP,... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394126 Mon, 01 Jan 2001 07:00:00 +0100 394126 http://www.medworm.com/index.php?rid=394125&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11407112%26dopt%3DAbstract Authors: Coote JG The success of a bacterial pathogen may depend on its ability to sense and respond to different environments. This is particularly true of those pathogens whose survival depends on adaptation to different niches both within and outside the host. Members of the genus Bordetella cause infections in humans, other animals and birds. Two closely related species, B. pertussis and B. bronchiseptica, cause respiratory disease and express a similar range of virulence factors during infection, but exhibit different host ranges and responses to environmental change. B. pertussis has no known reservoir other than humans and is assumed to be transmitted directly via aerosol droplets between hosts. B. bronchiseptica, on the other hand, has the potential to survive and grow in the n... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394125 Mon, 01 Jan 2001 07:00:00 +0100 394125 http://www.medworm.com/index.php?rid=394124&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11407113%26dopt%3DAbstract Authors: Robinson NJ, Whitehall SK, Cavet JS Bacterial metallothioneins bind, sequester and buffer excess intracellular zinc. At present, the vast majority of the available experimental data relate to cyanobacterial metallothionein, SmtA, from Synechococcus PCC 7942. SmtA is required for normal resistance to zinc and smtA-mediated zinc resistance has been used as a selectable marker. The imidazole groups of histidine residues, in addition to the thiol groups of cysteine residues, co-ordinate zinc in bacterial metallothioneins. The structure of bacterial metallothionein must facilitate some discrimination between 'adventitious' and 'adventageous' zinc-binding sites such that under excess zinc conditions metal is predominantly scavenged from the former. It remains unclear whether or not ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394124 Mon, 01 Jan 2001 07:00:00 +0100 394124 http://www.medworm.com/index.php?rid=394123&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11407114%26dopt%3DAbstract Authors: Rowbury RJ The work reported here follows from the proposal that, for efficient induction of numerous extracellular stress responses, cultures contain extracellular stress-sensing molecules, termed extracellular sensing components (ESCs). These are directly converted to extracellular induction components (EICs) by stresses, thus providing an early warning system against stress, with very rapid responses occurring on exposure to increasing levels of stress. Although some stress responses appear to involve activation of intracellular sensors, the proposed ESCs and EICs function for many stress tolerance and sensitization responses and for several cross-tolerance and cross-sensitization responses. Because EICs can induce responses in unstressed cells, and because they are small m... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394123 Mon, 01 Jan 2001 07:00:00 +0100 394123 http://www.medworm.com/index.php?rid=394122&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11407115%26dopt%3DAbstract Authors: Hecker M, Völker U One of the strongest and most noticeable responses of a Bacillus subtilis cell to a range of stress and starvation conditions is the dramatic induction of a large number of general stress proteins. The alternative sigma factor sigma B is responsible for the induction of the genes encoding these general stress proteins that occurs following heat, ethanol, salt or acid stress, or during energy depletion. sigma B was detected more than 20 years ago by Richard Losick and William Haldenwang as the first alternative sigma factor of bacteria, but interest in sigma B declined after it was realized that sigma B is not involved in sporulation. It later turned out that sigma B, whose activity itself is tightly controlled, is absolutely required for the induction of th... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394122 Mon, 01 Jan 2001 07:00:00 +0100 394122 http://www.medworm.com/index.php?rid=394121&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11407116%26dopt%3DAbstract Authors: Lund PA Protein folding in the cell, long thought to be a spontaneous process, in fact often requires the assistance of molecular chaperones. This is thought to be largely because of the danger of incorrect folding and aggregation of proteins, which is a particular problem in the crowded environment of the cell. Molecular chaperones are involved in numerous processes in bacterial cells, including assisting the folding of newly synthesized proteins, both during and after translation; assisting in protein secretion, preventing aggregation of proteins on heat shock, and repairing proteins that have been damaged or misfolded by stresses such as a heat shock. Within the cell, a balance has to be found between refolding of proteins and their proteolytic degradation, and molecular ch... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394121 Mon, 01 Jan 2001 07:00:00 +0100 394121 http://www.medworm.com/index.php?rid=394120&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11450107%26dopt%3DAbstract Authors: Blomfield IC The ability of bacterial pathogens to bind to the host mucosa is a critical step in the pathogenesis of many bacterial infections and, for Escherichia coli, a large number of different fimbrial adhesins have been implicated as virulence factors. In this chapter, our current understanding of the regulatory mechanisms that control the expression of two of the best characterized fimbrial adhesins, pyelonephritis-associated pilus (encoded by pap) and the type 1 fimbria (encoded by fim), will be described. The expression of both fimbrial adhesins is controlled by phase variation (the reversible and apparently random switching between expressing ('on') and non-expressing ('off') states), and is regulated in response to environmental conditions. The phase variation of pa... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394120 Mon, 01 Jan 2001 07:00:00 +0100 394120 http://www.medworm.com/index.php?rid=394119&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11450108%26dopt%3DAbstract We describe the ways in which genetics has shown (or not) if, and how, particular metal uptake and/or metal-mediated signalling pathways are required for the symbiotic interaction with legumes. PMID: 11450108 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394119 Mon, 01 Jan 2001 07:00:00 +0100 394119 http://www.medworm.com/index.php?rid=394118&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11450109%26dopt%3DAbstract Authors: Zhulin IB Chemotaxis transducers are specialized receptors that microorganisms use in order to sense the environment in directing their motility to favorable niches. The Escherichia coli transducers are models for studying the sensory and signaling events at the molecular level. Extensive studies in other organisms and the arrival of genomics has resulted in the accumulation of sequences of many transducer genes, but they are not fully understood. In silico analysis provides some assistance in classification of various transducers from different species and in predicting their function. All transducers contain two structural modules: a conserved C-terminal multidomain module, which is a signature element of the transducer superfamily, and a variable N-terminal module, which is... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394118 Mon, 01 Jan 2001 07:00:00 +0100 394118 http://www.medworm.com/index.php?rid=394117&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11450110%26dopt%3DAbstract Authors: Swift S, Downie JA, Whitehead NA, Barnard AM, Salmond GP, Williams P The discovery that bacterial cells can communicate with each other has led to the realization that bacteria are capable of exhibiting much more complex patterns of co-operative behaviour than would be expected for simple unicellular microorganisms. Now generically termed 'quorum sensing', bacterial cell-to-cell communication enables a bacterial population to mount a unified response that is advantageous to its survival by improving access to complex nutrients or environmental niches, collective defence against other competitive microorganisms or eukaryotic host defence mechanisms and optimization of population survival by differentiation into morphological forms better adapted to combating environmental threa... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394117 Mon, 01 Jan 2001 07:00:00 +0100 394117 http://www.medworm.com/index.php?rid=394116&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11450111%26dopt%3DAbstract Authors: Holms H Flux analysis (FA) is a means of organizing data to show flux through the central metabolic pathways (CMPs). It quantifies flux from uptake of carbon to the outputs of the CMPs, which are the precursors used for biosynthesis, acetate excretion and CO2. Fluxes to precursors reflect the commands of the genome and acetate excretion balances fluxes to precursor supply when uptake exceeds the capacity of the CMPs to allocate carbon in exactly the correct amount to each precursor. No other products have been detected in 11 phenotypes of Escherichia coli ML308. FA of each of these 11 phenotypes (with some additional variations in culture conditions, some selected mutations and one genetic construct) are shown as flux (mol (kg dry weight biomass)-1 h-1) and are the starting po... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394116 Mon, 01 Jan 2001 07:00:00 +0100 394116 http://www.medworm.com/index.php?rid=394115&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D11450112%26dopt%3DAbstract Authors: Potter L, Angove H, Richardson D, Cole J In contrast to the bacterial assimilatory and membrane-associated, respiratory nitrate reductases that have been studied for many years, it is only recently that periplasmic nitrate reductases have attracted growing interest. Recent research has shown that these soluble proteins are widely distributed, but vary greatly between species. All of those so far studied include four essential components: the periplasmic molybdoprotein, NapA, which is associated with a small, di-haem cytochrome, NapB; a putative quinol oxidase, NapC; and a possible pathway-specific chaperone, NapD. At least five other components have been found in different species. Other variations between species include the location of the nap genes on chromosomal or extrach... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394115 Mon, 01 Jan 2001 07:00:00 +0100 394115 http://www.medworm.com/index.php?rid=394135&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907549%26dopt%3DAbstract Authors: Whiteford JR, Thurston CF The types, economic significance and methods of production of the principal cultivated mushrooms are described in outline. These organisms are all less than ideal for conventional genetic analysis and breeding, so molecular methods afford a particular opportunity to advance our understanding of their biology and potentially give the prospect of improvement by gene manipulation. The sequences described are limited to those found in GenBank by August 1999. The gene sequences isolated from the white button mushroom Agaricus bisporus, the shiitake Lentinula edodes, the oyster mushrooms Pleurotus spp., the paddy straw mushroom Volvariella volvacea and the enotake Flammulina velutipes are described. The largest group are genes from A. bisporus, which includ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394135 Sat, 01 Jan 2000 07:00:00 +0100 394135 http://www.medworm.com/index.php?rid=394134&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907550%26dopt%3DAbstract Authors: Tannock GW The intestinal microflora provides opportunities for microbial physiological research. The metabolic interactions of bacterial inhabitants of the intestinal community, bacterial bioenergetics, preferential utilization of substrates as energy sources by specific bacterial species, and intercellular signalling are among the topics of challenging research awaiting the attention of microbial physiologists. PMID: 10907550 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394134 Sat, 01 Jan 2000 07:00:00 +0100 394134 http://www.medworm.com/index.php?rid=394133&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907551%26dopt%3DAbstract Authors: Hodgson DA Streptomycetes are Gram-positive bacteria with a unique capacity for the production of a multitude of varied and complex secondary metabolites. They also have a complex life cycle including differentiation into at least three distinct cell types. Whilst much attention has been paid to the pathways and regulation of secondary metabolism, less has been paid to the pathways and the regulation of primary metabolism, which supplies the precursors. With the imminent completion of the total genome sequence of Streptomyces coelicolor A3(2), we need to understand the pathways of primary metabolism if we are to understand the role of newly discovered genes. This review is written as a contribution to supplying these wants. Streptomycetes inhabit soil, which, because of the hi... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394133 Sat, 01 Jan 2000 07:00:00 +0100 394133 http://www.medworm.com/index.php?rid=394132&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907552%26dopt%3DAbstract Authors: Quivey RG, Kuhnert WL, Hahn K The strategies employed by oral streptococci to resist the inimical influences of acidification reflect the diverse and dynamic niches of the human mouth. All of the oral streptococci are capable of rapid degradation of sugar to acidic end-products. As a result, the pH value of their immediate environment can plummet to levels where glycolysis and growth cease. At this point, the approaches for survival in acid separate the organisms. Streptococcus mutans, for example, relies on its F-ATPase, to protect itself from acidification by pumping protons out of the cells. S. salivarius responds by degrading urea to ammonia and S. sanguis produces ammonia by arginolysis. The mechanisms by which these organisms regulate their particular escape route are no... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394132 Sat, 01 Jan 2000 07:00:00 +0100 394132 http://www.medworm.com/index.php?rid=394131&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907553%26dopt%3DAbstract Authors: Eide DJ Metal ions such as iron, copper, manganese, and zinc are essential nutrients for all eukaryotic microorganisms. Therefore, these organisms possess efficient uptake mechanisms to obtain these nutrients from their extracellular environment. Metal ions must also be transported into intracellular organelles where they function as catalytic and structural cofactors for compartmentalized enzymes. Thus, intracellular transport mechanisms are also present. When present in high levels, metal ions can also be toxic, so their uptake and intracellular transport is tightly regulated at both transcriptional and post-transcriptional levels to limit metal ion overaccumulation and facilitate storage and sequestration. Remarkable molecular insight into these processes has come from rece... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394131 Sat, 01 Jan 2000 07:00:00 +0100 394131 http://www.medworm.com/index.php?rid=394130&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907554%26dopt%3DAbstract Authors: De Luca NG, Wood PM Almost all iron uptake by fungi involves reduction from Fe(III) to Fe(II) in order to facilitate ligand exchange. This leads to two mechanisms: uptake before reduction, or reduction before uptake. Many fungi secrete specific hydroxamate siderophores when short of iron. The mechanism with uptake before reduction is described in the context of siderophore synthesis and usage, since it applies to many (but not all) siderophores. The hydroxamate functional group is synthesized from ornithine by N5 hydroxylation and acylation. In most fungal siderophores, two or three modified ornithines are joined together by a non-ribosomal peptide synthetase. The transcription of these genes is regulated by an iron activated repressor. There is evidence that the iron-free sid... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394130 Sat, 01 Jan 2000 07:00:00 +0100 394130 http://www.medworm.com/index.php?rid=394129&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907555%26dopt%3DAbstract Authors: Cortassa S, Aon JC, Aon MA, Spencer JF The dynamics of metabolism has been shown to be involved in the triggering of events that are concurrent with sporulation of the budding yeast Saccharomyces cerevisiae. Indeed, quantitative correlations have been demonstrated between sporulation and the rate of carbon substrate or oxygen consumption, and the fluxes through gluconeogenic and glyoxylate cycle pathways. The results suggest that an imbalance between catabolic and anabolic fluxes influences the occurrence of the differentiation process. The hypothesis that the initiation of sporulation is triggered by the accumulation of an intracellular metabolite is confronted with the notion that intermediary metabolism and the expression of genes involved in sporulation interact to trigger... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394129 Sat, 01 Jan 2000 07:00:00 +0100 394129 http://www.medworm.com/index.php?rid=394128&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907556%26dopt%3DAbstract Authors: Poole P, Allaway D One of the paradigms of symbiotic nitrogen fixation has been that bacteroids reduce N2 to ammonium and secrete it without assimilation into amino acids. This has recently been challenged by work with soybeans showing that only alanine is excreted in 15N2 labelling experiments. Work with peas shows that the bacteroid nitrogen secretion products during in vitro experiments depend on the experimental conditions. There is a mixed secretion of both ammonium and alanine depending critically on the concentration of bacteroids and ammonium concentration. The pathway of alanine synthesis has been shown to be via alanine dehydrogenase, and mutation of this enzyme indicates that in planta there is likely to be mixed secretion of ammonium and alanine. Alanine synthesis ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394128 Sat, 01 Jan 2000 07:00:00 +0100 394128 http://www.medworm.com/index.php?rid=394127&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10907557%26dopt%3DAbstract Authors: Poole RK, Cook GM Bacteria are the most remarkable organisms in the biosphere, surviving and growing in environments that support no other life forms. Underlying this ability is a flexible metabolism controlled by a multitude of environmental sensors and regulators of gene expression. It is not surprising, therefore, that bacterial respiration is complex and highly adaptable: virtually all bacteria have multiple, branched pathways for electron transfer from numerous low-potential reductants to several terminal electron acceptors. Such pathways, particularly those involved in anaerobic respiration, may involve periplasmic components, but the respiratory apparatus is largely membrane-bound and organized such that electron flow is coupled to proton (or sodium ion) transport, gene... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394127 Sat, 01 Jan 2000 07:00:00 +0100 394127 http://www.medworm.com/index.php?rid=394141&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10500843%26dopt%3DAbstract Authors: Oliver AL, Anderson BN, Roddick FA L-Phenylacetylcarbinol (L-PAC) is the precursor for L-ephedrine and D-pseudoephedrine, alkaloids possessing alpha- and beta-adrenergic activity. The most commonly used method for production of L-PAC is a biological method whereby the enzyme pyruvate decarboxylase (PDC) decarboxylates pyruvate and then condenses the product with added benzaldehyde. The process may be undertaken by either whole cells or purified PDC. If whole cells are used, the biomass may be grown and allowed to synthesize endogenous pyruvate, or the cells may be used as a catalyst only, with both pyruvate and benzaldehyde being added. Several yeast species have been investigated with regard to L-PAC-producing potential; the most commonly used organisms are strains of Sacchar... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394141 Fri, 01 Jan 1999 07:00:00 +0100 394141 http://www.medworm.com/index.php?rid=394140&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10500844%26dopt%3DAbstract Authors: Gadd GM The production of organic acids by fungi has profound implications for metal speciation, physiology and biogeochemical cycles. Biosynthesis of oxalic acid from glucose occurs by hydrolysis of oxaloacetate to oxalate and acetate catalysed by cytosolic oxaloacetase, whereas on citric acid, oxalate production occurs by means of glyoxylate oxidation. Citric acid is an intermediate in the tricarboxylic acid cycle, with metals greatly influencing biosynthesis: growth limiting concentrations of Mn, Fe and Zn are important for high yields. The metal-complexing properties of these organic acids assist both essential metal and anionic (e.g. phosphate) nutrition of fungi, other microbes and plants, and determine metal speciation and mobility in the environment, including transfer... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394140 Fri, 01 Jan 1999 07:00:00 +0100 394140 http://www.medworm.com/index.php?rid=394139&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10500845%26dopt%3DAbstract Authors: Barer MR, Harwood CR Renewed interest in the relationships between viability and culturability in bacteria stems from three sources: (1) the recognition that there are many bacteria in the biosphere that have never been propagated or characterized in laboratory culture; (2) the proposal that some readily culturable bacteria may respond to certain stimuli by entering a temporarily non-culturable state termed 'viable but non-culturable' (VBNC) by some authors; and (3) the development of new techniques that facilitate demonstration of activity, integrity and composition of non-culturable bacterial cells. We review the background to these areas of interest emphasizing the view that, in an operational context, the term VBNC is self-contradictory (Kell et al., 1998) and the likely d... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394139 Fri, 01 Jan 1999 07:00:00 +0100 394139 http://www.medworm.com/index.php?rid=394138&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10500846%26dopt%3DAbstract Authors: Grebe TW, Stock JB Signal transduction in microorganisms and plants is often mediated by His-Asp phosphorelay systems. Two conserved families of proteins are centrally involved: histidine protein kinases and phospho-aspartyl response regulators. The kinases generally function in association with sensory elements that regulate their activities in response to environmental signals. A sequence analysis with 348 histidine kinase domains reveals that this family consists of distinct subgroups. A comparative sequence analysis with 298 available receiver domain sequences of cognate response regulators demonstrates a significant correlation between kinase and regulator subfamilies. These findings suggest that different subclasses of His-Asp phosphorelay systems have evolved independen... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394138 Fri, 01 Jan 1999 07:00:00 +0100 394138 http://www.medworm.com/index.php?rid=394137&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10500847%26dopt%3DAbstract Authors: Armitage JP Many, if not most, bacterial species swim. The synthesis and operation of the flagellum, the most complex organelle of a bacterium, takes a significant percentage of cellular energy, particularly in the nutrient limited environments in which many motile species are found. It is obvious that motility accords cells a survival advantage over non-motile mutants under normal, poorly mixed conditions and is an important determinant in the development of many associations between bacteria and other organisms, whether as pathogens or symbionts and in colonization of niches and the development of biofilms. This survival advantage is the result of sensory control of swimming behaviour. Although too small to sense a gradient along the length of the cell, and unable to swim gr... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394137 Fri, 01 Jan 1999 07:00:00 +0100 394137 http://www.medworm.com/index.php?rid=394136&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D10500848%26dopt%3DAbstract Authors: Berry RM, Armitage JP The bacterial flagellum is probably the most complex organelle found in bacteria. Although the ribosome may be made of slightly more subunits, the bacterial flagellum is a more organized and complex structure. The limited number of flagella must be targeted to the correct place on the cell membrane and a structure with cytoplasmic, cytoplasmic membrane, outer membrane and extracellular components must be assembled. The process of controlled transcription and assembly is still not fully understood. Once assembled, the motor complex in the cytoplasmic membrane rotates, driven by the transmembrane ion gradient, at speeds that can reach many 100 Hz, driving the bacterial cell at several body lengths a second. This coupling of an electrochemical gradient to me... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394136 Fri, 01 Jan 1999 07:00:00 +0100 394136 http://www.medworm.com/index.php?rid=394156&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9328645%26dopt%3DAbstract Authors: Lin JT, Stewart V Nitrate is a significant nitrogen source for plants and microorganisms. Recent molecular genetic analyses of representative bacterial species have revealed structural and regulatory genes responsible for the nitrate-assimilation phenotype. Together with results from physiological and biochemical studies, this information has unveiled fundamental aspects of bacterial nitrate assimilation and provides the foundation for further investigations. Well-studied genera are: the cyanobacteria, including the unicellular Synechococcus and the filamentous Anabaena; the gamma-proteobacteria Klebsiella and Azotobacter; and a Gram-positive bacterium, Bacillus. Nitrate uptake in most of these groups seems to involve a periplasmic binding protein-dependent system that presuma... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394156 Thu, 01 Jan 1998 07:00:00 +0100 394156 http://www.medworm.com/index.php?rid=394155&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9328646%26dopt%3DAbstract Authors: Mitchell WJ The solvent-forming clostridia have attracted interest because of their ability to convert a range of carbohydrates to end-products such as acetone, butanol and ethanol. Polymeric substrates such as cellulose, hemicellulose and starch are degraded by extracellular enzymes. The majority of cellulolytic clostridia, typified by Clostridium thermocellum, produce a multi-enzyme cellulase complex in which the organization of components is critical for activity against the crystalline substrate. A variety of enzymes involved in degradation of hemicellulose and starch have been identified in different strains. The products of degradation, and other soluble substrates, are accumulated via membrane-bound transport systems which are generally poorly characterized. It is clear... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394155 Thu, 01 Jan 1998 07:00:00 +0100 394155 http://www.medworm.com/index.php?rid=394154&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9328647%26dopt%3DAbstract Authors: Daffé M, Draper P The review discusses current knowledge of the biosynthesis, composition and arrangement of the mycobacterial envelope, describes the biological activities of the constituents and considers how these activities may be relevant to the pathology of mycobacterial disease. The envelope possesses three structural components: plasma membrane, wall and capsule. Although the major biomolecules occurring in each of these parts are known, the distribution of numerous minor substances is poorly understood; an attempt has been made to assign them to particular positions on rational grounds. The plasma membrane appears to be a typical bacterial membrane but, though vital to the mycobacterium, probably plays little part in pathological processes. The wall partly resembles ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394154 Thu, 01 Jan 1998 07:00:00 +0100 394154 http://www.medworm.com/index.php?rid=394153&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9328648%26dopt%3DAbstract Authors: Russell JB, Diez-Gonzalez F Anaerobic habitats often have low pH and high concentrations of fermentation acids, and these conditions can inhibit the growth of many bacteria. The toxicity of fermentation acids at low pH was traditionally explained by an uncoupling mechanism. Undissociated fermentation acids can pass across the cell membrane and dissociate in the more alkaline interior, but there is little evidence that they can act in a cyclic manner to dissipate protonmotive force. Fermentation acid dissociation in the more alkaline interior causes an accumulation of the anionic species, and this accumulation is dependent on the pH gradient (delta pH) across the membrane. Fermentation acid-resistant bacteria have low delta pH and are able to generate ATP and grow with a low in... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394153 Thu, 01 Jan 1998 07:00:00 +0100 394153 http://www.medworm.com/index.php?rid=394152&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9328649%26dopt%3DAbstract Authors: Friedrich CG Reduced inorganic sulfur compounds are oxidized by members of the domains Archaea and Bacteria. These compounds are used as electron donors for anaerobic phototrophic and aerobic chemotrophic growth, and are mostly oxidized to sulfate. Different enzymes mediate the conversion of various reduced sulfur compounds. Their physiological function in sulfur oxidation is considered (i) mostly from the biochemical characterization of the enzymatic reaction, (ii) rarely from the regulation of their formation, and (iii) only in a few cases from the mutational gene inactivation and characterization of the resulting mutant phenotype. In this review the sulfur-metabolizing reactions of selected phototrophic and of chemotrophic prokaryotes are discussed. These comprise an archae... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394152 Thu, 01 Jan 1998 07:00:00 +0100 394152 http://www.medworm.com/index.php?rid=394151&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9328650%26dopt%3DAbstract Authors: Lloyd D The time structure of a biological system is at least as intricate as its spatial structure. Whereas we have detailed information about the latter, our understanding of the former is still rudimentary. As techniques for monitoring intracellular processes continuously in single cells become more refined, it becomes increasingly evident that periodic behaviour abounds in all time domains. Circadian timekeeping dominates in natural environments. Here the free-running period is about 24 h. Circadian rhythms in eukaryotes and prokaryotes allow predictive matching of intracellular states with environmental changes during the daily cycles. Unicellular organisms provide excellent systems for the study of these phenomena, which pervade all higher life forms. Intracellular timek... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394151 Thu, 01 Jan 1998 07:00:00 +0100 394151 http://www.medworm.com/index.php?rid=394150&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9328651%26dopt%3DAbstract Authors: Sasikala C, Ramana CV Anoxygenic phototrophic bacteria play an important role in anaerobic nutritional cycles. The most readily used and widely studied carbon sources for growth of these bacteria are organic acids and a few carbohydrates. In this review we survey the growing knowledge on the metabolism of a number of other carbon sources, particularly polymers (starch, poly(3-hydroxyalkanoates)), aromatic compounds (natural and xenobiotic), one-carbon compounds, alcohols, aliphatic hydrocarbons and higher fatty acids, and their influence on various cellular activities of purple non-sulfur bacteria. We also discuss the possible exploitations in various biotechnological processes of this group of microorganisms while metabolizing unusual carbon compounds. PMID: 9328651 [PubM... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394150 Thu, 01 Jan 1998 07:00:00 +0100 394150 http://www.medworm.com/index.php?rid=394149&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889976%26dopt%3DAbstract Authors: Goodwin PM, Anthony C Pyrrolo-quinoline quinone (PQQ) is the non-covalently bound prosthetic group of many quinoproteins catalysing reactions in the periplasm of Gram-negative bacteria. Most of these involve the oxidation of alcohols or aldose sugars. PQQ is formed by fusion of glutamate and tyrosine, but details of the biosynthetic pathway are not known; a polypeptide precursor in the cytoplasm is probably involved, the completed PQQ being transported into the periplasm. In addition to the soluble methanol dehydrogenase of methylotrophs, there are three classes of alcohol dehydrogenases; type I is similar to methanol dehydrogenase; type II is a soluble quinohaemoprotein, having a C-terminal extension containing haem C; type III is similar but it has two additional subunits (o... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394149 Thu, 01 Jan 1998 07:00:00 +0100 394149 http://www.medworm.com/index.php?rid=394148&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889978%26dopt%3DAbstract Authors: Kelly DJ Helicobacter pylori is a spiral Gram-negative microaerophilic bacterium that causes one of the most common infections in humans; approximately 30-50% of individuals in Western Europe are infected and the figure is nearly 100% in the developing world. It is recognized as the major aetiological factor in chronic active type B gastritis, and gastric and duodenal ulceration and as a risk factor for gastric cancer. H. pylori normally inhabits the mucus-lined surface of the antrum of the human stomach where it induces a mild inflammation, but its presence is otherwise usually asymptomatic. A variety of virulence factors appear to play a role in pathogenesis. These include the vacuolating cytotoxin VacA, cytotoxin-associated proteins, urease and motility. All are under inten... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394148 Thu, 01 Jan 1998 07:00:00 +0100 394148 http://www.medworm.com/index.php?rid=394147&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889979%26dopt%3DAbstract Authors: Delgado MJ, Bedmar EJ, Downie JA Rhizobia fix nitrogen in a symbiotic association with leguminous plants and this occurs in nodules. A low-oxygen environment is needed for nitrogen fixation, which paradoxically has a requirement for rapid respiration to produce ATP. These conflicting demands are met by control of oxygen flux and production of leghaemoglobin (an oxygen carrier) by the plant, coupled with the expression of a high-affinity oxidase by the nodule bacteria (bacteroids). Many of the bacterial genes encoding cytochrome synthesis and assembly have been identified in a variety of rhizobial strains. Nitrogen-fixing bacteroids use a cytochrome cbb3-type oxidase encoded by the fixNOQP operon; electron transfer to this high-affinity oxidase is via the cytochrome bc1 complex... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394147 Thu, 01 Jan 1998 07:00:00 +0100 394147 http://www.medworm.com/index.php?rid=394146&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889980%26dopt%3DAbstract Authors: Spector MP Salmonella serovars are common etiologic agents of intestinal-based disease of animals and humans. As a result of their lifestyle, salmonellae occupy and survive in a wide range of niches where they can encounter an even broader range of environmental stresses. One of the most common stresses is starvation for an essential nutrient such as a carbon/energy (C)-source. The genetic and physiologic changes that the bacterium undergoes in response to starvation-stress are referred to as the starvation-stress response or SSR. The genetic loci whose expression increases in response to the starvation-stress compose the SSR stimulon. Several loci of the SSR stimulon have been identified in Salmonella typhimurium and grouped, based on putative or known functions or products, ... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394146 Thu, 01 Jan 1998 07:00:00 +0100 394146 http://www.medworm.com/index.php?rid=394145&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889981%26dopt%3DAbstract Authors: Andrews SC Iron is an essential nutrient for nearly all organisms but presents problems of toxicity, poor solubility and low availability. These problems are alleviated through the use of iron-storage proteins. Bacteria possess two types of iron-storage protein, the haem-containing bacterioferritins and the haem-free ferritins. These proteins are widespread in bacteria, with at least 39 examples known so far in eubacteria and archaebacteria. The bacterioferritins and ferritins are distantly related but retain similar structural and functional properties. Both are composed of 24 identical or similar subunits (approximately 19 kDa) that form a roughly spherical protein (approximately 450 kDa, approximately 120 A diameter) containing a large hollow centre (approximately 80 A diam... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394145 Thu, 01 Jan 1998 07:00:00 +0100 394145 http://www.medworm.com/index.php?rid=394144&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889982%26dopt%3DAbstract Authors: Koch AL Bacteria in the modern taxonomic sense are one of the three Domains. They must have split from the other two after the bulk of the development of biochemistry and cell biology had taken place. Up to the time of the Last Universal Ancestor (LUA) the world had been monophyletic with little stable diversity. This is to say that as advances took place the older forms were eliminated and diversity was only temporary. Two kinds of events could, in principle, permit stable diversity to arise. One kind occurs when two nearly simultaneous, different advances occur, both of which overcome the same problem. While the previous type would be supplanted, if the new types did not compete with each other, new niches and habitats could lead to stable diversity. The second kind is a sal... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394144 Thu, 01 Jan 1998 07:00:00 +0100 394144 http://www.medworm.com/index.php?rid=394143&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889983%26dopt%3DAbstract Authors: Krulwich TA, Ito M, Gilmour R, Hicks DB, Guffanti AA The challenge of maintaining a cytoplasmic pH that is much lower than the external pH is central to the adaptation of extremely alkaliphilic Bacillus species to growth at pH values above 10. The success with which this challenge is met may set the upper limit of pH for growth in these bacteria, all of which also exhibit a low content of basic amino acids in proteins or protein segments that are exposed to the outside bulk phase liquid. The requirement for an active Na(+)-dependent cycle and possible roles of acidic cell wall components in alkaliphile pH homeostasis are reviewed. The gene loci that encode Na+/H+ antiporters that function in the active cycle are described and compared with the less Na(+)-specific homologues th... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394143 Thu, 01 Jan 1998 07:00:00 +0100 394143 http://www.medworm.com/index.php?rid=394142&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D9889977%26dopt%3DAbstract Authors: Saier MH Although enzymes catalyzing chemical reactions have long been classified according to the system developed by the Enzyme Commission (EC), no comparable system has been developed or proposed for transport proteins catalyzing transmembrane vectorial reactions. We here propose a comprehensive system, designated the Transport Commission (TC) system, based both on function and phylogeny. The TC system initially categorizes permeases according to mode of transport and energy coupling mechanism, and each category is assigned a one-component TC number (W). The secondary level of classification corresponds to the phylogenetic family (or superfamily) to which a particular permease is assigned, and each family is assigned a two-component TC number (W.X). The third level of class... Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394142 Thu, 01 Jan 1998 07:00:00 +0100 394142 http://www.medworm.com/index.php?rid=394162&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8922117%26dopt%3DAbstract Authors: Wessels JG PMID: 8922117 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394162 Wed, 01 Jan 1997 07:00:00 +0100 394162 http://www.medworm.com/index.php?rid=394161&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8922118%26dopt%3DAbstract Authors: Butler CS, Mason JR PMID: 8922118 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394161 Wed, 01 Jan 1997 07:00:00 +0100 394161 http://www.medworm.com/index.php?rid=394159&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8922119%26dopt%3DAbstract Authors: Zocher R, Keller U PMID: 8922119 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394159 Wed, 01 Jan 1997 07:00:00 +0100 394159 http://www.medworm.com/index.php?rid=394158&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8922120%26dopt%3DAbstract Authors: Slater JH, Bull AT, Hardman DJ PMID: 8922120 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394158 Wed, 01 Jan 1997 07:00:00 +0100 394158 http://www.medworm.com/index.php?rid=394157&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8922121%26dopt%3DAbstract Authors: Beveridge TJ, Hughes MN, Lee H, Leung KT, Poole RK, Savvaidis I, Silver S, Trevors JT PMID: 8922121 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394157 Wed, 01 Jan 1997 07:00:00 +0100 394157 http://www.medworm.com/index.php?rid=394173&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8540419%26dopt%3DAbstract Authors: Tomme P, Warren RA, Gilkes NR PMID: 8540419 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394173 Sun, 01 Jan 1995 07:00:00 +0100 394173 http://www.medworm.com/index.php?rid=394172&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8540420%26dopt%3DAbstract Authors: Hancock RE, Falla T, Brown M PMID: 8540420 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394172 Sun, 01 Jan 1995 07:00:00 +0100 394172 http://www.medworm.com/index.php?rid=394170&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8540421%26dopt%3DAbstract Authors: Inoue Y, Kimura A PMID: 8540421 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394170 Sun, 01 Jan 1995 07:00:00 +0100 394170 http://www.medworm.com/index.php?rid=394168&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8540422%26dopt%3DAbstract Authors: Hall HK, Karem KL, Foster JW PMID: 8540422 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394168 Sun, 01 Jan 1995 07:00:00 +0100 394168 http://www.medworm.com/index.php?rid=394166&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8540423%26dopt%3DAbstract Authors: Galinski EA PMID: 8540423 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394166 Sun, 01 Jan 1995 07:00:00 +0100 394166 http://www.medworm.com/index.php?rid=394164&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8540424%26dopt%3DAbstract Authors: Smith RJ PMID: 8540424 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394164 Sun, 01 Jan 1995 07:00:00 +0100 394164 http://www.medworm.com/index.php?rid=394185&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D7942312%26dopt%3DAbstract Authors: Payne JW, Smith MW PMID: 7942312 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394185 Sat, 01 Jan 1994 07:00:00 +0100 394185 http://www.medworm.com/index.php?rid=394182&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D7942313%26dopt%3DAbstract Authors: Dijksterhuis J, Veenhuis M, Harder W, Nordbring-Hertz B PMID: 7942313 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394182 Sat, 01 Jan 1994 07:00:00 +0100 394182 http://www.medworm.com/index.php?rid=394181&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D7942314%26dopt%3DAbstract Authors: Fiechter A, Sonnleitner B PMID: 7942314 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394181 Sat, 01 Jan 1994 07:00:00 +0100 394181 http://www.medworm.com/index.php?rid=394179&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D7942315%26dopt%3DAbstract Authors: Satta G, Fontana R, Canepari P PMID: 7942315 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394179 Sat, 01 Jan 1994 07:00:00 +0100 394179 http://www.medworm.com/index.php?rid=394177&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D7942316%26dopt%3DAbstract Authors: Matsushita K, Toyama H, Adachi O PMID: 7942316 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394177 Sat, 01 Jan 1994 07:00:00 +0100 394177 http://www.medworm.com/index.php?rid=394175&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D7942317%26dopt%3DAbstract Authors: Plateau P, Blanquet S PMID: 7942317 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394175 Sat, 01 Jan 1994 07:00:00 +0100 394175 http://www.medworm.com/index.php?rid=394202&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8310879%26dopt%3DAbstract Authors: Hoch JA PMID: 8310879 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394202 Fri, 01 Jan 1993 07:00:00 +0100 394202 http://www.medworm.com/index.php?rid=394200&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8310880%26dopt%3DAbstract Authors: Whitfield C, Valvano MA PMID: 8310880 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394200 Fri, 01 Jan 1993 07:00:00 +0100 394200 http://www.medworm.com/index.php?rid=394198&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8310881%26dopt%3DAbstract Authors: Sahm H, Rohmer M, Bringer-Meyer S, Sprenger GA, Welle R PMID: 8310881 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394198 Fri, 01 Jan 1993 07:00:00 +0100 394198 http://www.medworm.com/index.php?rid=394196&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8310882%26dopt%3DAbstract Authors: Fukuda H, Ogawa T, Tanase S PMID: 8310882 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394196 Fri, 01 Jan 1993 07:00:00 +0100 394196 http://www.medworm.com/index.php?rid=394194&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8310883%26dopt%3DAbstract Authors: Heider J, Böck A PMID: 8310883 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394194 Fri, 01 Jan 1993 07:00:00 +0100 394194 http://www.medworm.com/index.php?rid=394192&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8452091%26dopt%3DAbstract Authors: Meighen EA, Dunlap PV PMID: 8452091 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394192 Fri, 01 Jan 1993 07:00:00 +0100 394192 http://www.medworm.com/index.php?rid=394190&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8452092%26dopt%3DAbstract Authors: Wessels JG PMID: 8452092 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394190 Fri, 01 Jan 1993 07:00:00 +0100 394190 http://www.medworm.com/index.php?rid=394188&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8452093%26dopt%3DAbstract Authors: Wolber PK PMID: 8452093 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394188 Fri, 01 Jan 1993 07:00:00 +0100 394188 http://www.medworm.com/index.php?rid=394187&cid=s_34426_77_f&fid=34426&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D8452094%26dopt%3DAbstract Authors: Gooday GW, Adams DJ PMID: 8452094 [PubMed - indexed for MEDLINE] (Source: Advances in Microbial Physiology) Advances in Microbial Physiology journals http://www.medworm.com/rss/comments.php?id=394187 Fri, 01 Jan 1993 07:00:00 +0100 394187