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 'Coordination Chemistry Reviews' source. Thu, 30 Jun 2011 05:26:34 +0100 http://www.medworm.com/index.php?rid=4893956&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21607119%26dopt%3DAbstract This article describes the basic nomenclature of pterin, their biological roles, structure, chemical synthesis and redox reactivity. In addition, the biosynthesis of pterins and current models of the molybdenum cofactor are discussed. PMID: 21607119 [PubMed - as supplied by publisher] (Source: Coordination Chemistry Reviews) Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=4893956 Sat, 30 Apr 2011 23:00:00 +0100 4893956 http://www.medworm.com/index.php?rid=4791917&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21516203%26dopt%3DAbstract Authors: Hille R, Nishino T, Bittner F Recent progress in our understanding of the structural and catalytic properties of molybdenum-containing enzymes in eukaryotes is reviewed, along with aspects of the biosynthesis of the cofactor and its insertion into apoprotein. PMID: 21516203 [PubMed - as supplied by publisher] (Source: Coordination Chemistry Reviews) Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=4791917 Sat, 30 Apr 2011 23:00:00 +0100 4791917 http://www.medworm.com/index.php?rid=4791916&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21528011%26dopt%3DAbstract Authors: Leimkühler S, Wuebbens MM, Rajagopalan KV Biosynthesis of the molybdenum cofactor in bacteria is described with a detailed analysis of each individual reaction leading to the formation of stable intermediates during the synthesis of molybdopterin from GTP. As a starting point, the discovery of molybdopterin and the elucidation of its structure through the study of stable degradation products are described. Subsequent to molybdopterin synthesis, the molybdenum atom is added to the molybdopterin dithiolene group to form the molybdenum cofactor. This cofactor is either inserted directly into specific molybdoenzymes or is further modified by the addition of nucleotides to the molybdopterin phosphate group or the replacement of ligands at the molybdenum center. PMID: 21528011 ... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=4791916 Sat, 30 Apr 2011 23:00:00 +0100 4791916 http://www.medworm.com/index.php?rid=4739829&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21503270%26dopt%3DAbstract Authors: Hu Y, Ribbe MW Biosynthesis of nitrogenase FeMoco is a highly complex process that requires, minimally, the participation of nifS, nifU, nifB, nifE, nifN, nifV, nifH, nifD and nifK gene products. Previous genetic analyses have identified the essential factors for the assembly of FeMoco; however, the exact functions of these factors and the precise sequence of events during the assembly process had remained unclear until recently, when a number of the biosynthetic intermediates of FeMoco were identified and characterized by combined biochemical, spectroscopic and structural analyses. This review gives a brief account of the recent progress toward understanding the assembly process of FeMoco, which has identified some important missing pieces of this biosynthetic puzzle. PMI... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=4739829 Fri, 22 Apr 2011 23:15:14 +0100 4739829 http://www.medworm.com/index.php?rid=4627070&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21423881%26dopt%3DAbstract Authors: Du J, Sono M, Dawson JH Preparation of heme model complexes is a challenging subject of long-standing interest for inorganic chemists. His93Gly sperm whale myoglobin (H93G Mb) has the proximal His replaced with the much smaller non-coordinating Gly. This leaves a cavity on the proximal side of the heme into which a wide variety of exogenous ligands can be delivered. The end result is a remarkably versatile scaffold for the preparation of model heme adducts to mimic the heme iron coordination structure of native heme proteins. In this review, we first summarize the quantitative evidence for differential ligand binding affinities of the proximal and distal pockets of the H93G Mb cavity mutant that facilitates the preparation of mixed-ligand derivatives. Then we review our use of... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=4627070 Thu, 24 Mar 2011 08:00:19 +0100 4627070 http://www.medworm.com/index.php?rid=4056833&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20936084%26dopt%3DAbstract Authors: Jurow M, Schuckman AE, Batteas JD, Drain CM The proposal that molecules can perform electronic functions in devices such as diodes, rectifiers, wires, capacitors, or serve as functional materials for electronic or magnetic memory, has stimulated intense research across physics, chemistry, and engineering for over 35 years. Because biology uses porphyrins and metalloporphyrins as catalysts, small molecule transporters, electrical conduits, and energy transducers in photosynthesis, porphyrins are an obvious class of molecules to investigate for molecular electronic functions. Of the numerous kinds of molecules under investigation for molecular electronics applications, porphyrins and their related macrocycles are of particular interest because they are robust and their electroni... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=4056833 Thu, 30 Sep 2010 23:00:00 +0100 4056833 http://www.medworm.com/index.php?rid=3896752&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20729977%26dopt%3DAbstract Authors: Ragsdale S PMID: 20729977 [PubMed - as supplied by publisher] (Source: Coordination Chemistry Reviews) Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=3896752 Wed, 25 Aug 2010 03:18:05 +0100 3896752 http://www.medworm.com/index.php?rid=3741210&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20607091%26dopt%3DAbstract Authors: Riordan CG This review traces the development and application of the tris(thioether)borate ligands, tripodal ligands with highly polarizable thioether donors. Areas of emphasis include the basic coordination chemistry of the mid-to-late first row transition metals (Fe, Ni, Co, Cu), and the role of the thioether substituent in directing complex formation, the modeling of zinc thiolate protein active sites, high-spin organo-iron and organo-cobalt chemistry, the preparation of monovalent complexes of Fe, Co and Ni, and dioxygen and sulfur activation by monovalent nickel complexes. PMID: 20607091 [PubMed - as supplied by publisher] (Source: Coordination Chemistry Reviews) Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=3741210 Sat, 10 Jul 2010 20:15:05 +0100 3741210 http://www.medworm.com/index.php?rid=3688102&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20563297%26dopt%3DAbstract Authors: Eckermann AL, Feld DJ, Shaw JA, Meade TJ Redox-active self-assembled monolayers (SAMs) provide an excellent platform for investigating electron transfer kinetics. Using a well-defined bridge, a redox center can be positioned at a fixed distance from the electrode and electron transfer kinetics probed using a variety of electrochemical techniques. Cyclic voltammetry, AC voltammetry, electrochemical impedance spectroscopy, and chronoamperometry are most commonly used to determine the rate of electron transfer of redox-activated SAMs. A variety of redox species have been attached to SAMs, and include transition metal complexes (e.g., ferrocene, ruthenium pentaammine, osmium bisbipyridine, metal clusters) and organic molecules (e.g., galvinol, C(60)). SAMs offer an ideal environme... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=3688102 Thu, 24 Jun 2010 00:33:07 +0100 3688102 http://www.medworm.com/index.php?rid=3284207&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20161508%26dopt%3DAbstract We report a quantitative theoretical analysis of long-range electron transfer through sensitizer wires bound in the active-site channel of cytochrome P450cam. Each sensitizer wire consists of a substrate group with high binding affinity for the enzyme active site connected to a ruthenium-diimine through a bridging aliphatic or aromatic chain. Experiments have revealed a dramatic dependence of electron transfer rates on the chemical composition of both the bridging group and the substrate. Using combined molecular dynamics simulations and electronic coupling calculations, we show that electron tunneling through perfluorinated aromatic bridges is promoted by enhanced superexchange coupling through virtual reduced states. In contrast, electron flow through aliphatic bridges occurs by hole-med... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=3284207 Mon, 01 Feb 2010 00:00:00 +0100 3284207 http://www.medworm.com/index.php?rid=3146525&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20047011%26dopt%3DAbstract Authors: Milacic V, Dou QP Although cisplatin plays a vital role in the treatment of several types of human cancer, its wide use is limited by the development of drug resistance and associated toxic side effects. Gold and gold complexes have been used to treat a wide range of ailments for many centuries. In recent years, the use of gold(III) complexes as an alternative to cisplatin treatment was proposed due to the similarities of gold and platinum. Gold(III) is isoelectronic with platinum(II) and gold(III) complexes have the same square-planar geometries as platinum(II) complexes, such as cisplatin. Although it was originally thought that gold(III) complexes might have the same molecular target as cisplatin, several lines of data indicated that proteins, rather than DNA, are targeted ... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=3146525 Thu, 01 Jan 2009 00:00:00 +0100 3146525 http://www.medworm.com/index.php?rid=2135202&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19169375%26dopt%3DAbstract Authors: Gokel GW, Daschbach MM Hydraphiles are synthetic ionophores that were designed to mimic some properties of protein channels that conduct such cations as sodium. They use macrocyclic (crown) polyethers as amphiphilic headgroups and as entry and exit portals. Their overall length is controlled by covalent links between the two headgroups (distal macrocycles) and the "central relay" unit, typically also an azacrown. The hydraphiles insert in the bilayer membranes of synthetic phospholipid vesicles or vital cells and mediate the transport of cations. The hydraphiles were intended to be models but they are functional channels. Because they are symmetric, they are non-rectifying but they show open-close behavior characteristic of natural channels. Because they are non-rectifying, wh... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=2135202 Tue, 01 Apr 2008 04:00:00 +0100 2135202 http://www.medworm.com/index.php?rid=2041734&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19081816%26dopt%3DAbstract Authors: Mullins CS, Pecoraro VL Recent advances in the study of the Oxygen Evolving Complex (OEC) of Photosystem II (PSII) include structural information attained from several X-ray crystallographic (XRD) and spectroscopic (XANES and EXAFS) investigations. The possible structural features gleaned from these studies have enabled synthetic chemists to design more accurate model complexes, which in turn, offer better insight into the possible pathways used by PSII to drive photosynthetic water oxidation catalysis. Mononuclear model compounds have been used to advance the knowledge base regarding the physical properties and reactivity of high-valent (Mn(IV) or Mn(V)) complexes. Such investigations have been especially important in regard to the manganyl (Mn(IV)=O or Mn(V) identical withO)... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=2041734 Fri, 01 Feb 2008 05:00:00 +0100 2041734 http://www.medworm.com/index.php?rid=1570472&cid=s_37313_51_f&fid=37313&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18496594%26dopt%3DAbstract Authors: Debus RJ Photosynthetic water oxidation is catalyzed by a unique Mn(4)Ca cluster in Photosystem II. The ligation environment of the Mn(4)Ca cluster optimizes the cluster's reactivity at each step in the catalytic cycle and minimizes the release of toxic, partly oxidized intermediates. However, our understanding of the cluster's ligation environment remains incomplete. Although the recent X-ray crystallographic structural models have provided great insight and are consistent with most conclusions of earlier site-directed mutagenesis studies, the ligation environments of the Mn(4)Ca cluster in the two available structural models differ in important respects. Furthermore, while these structural models and the earlier mutagenesis studies agree on the identity of most of the Mn(4)C... Coordination Chemistry Reviews journals http://www.medworm.com/rss/comments.php?id=1570472 Fri, 01 Feb 2008 05:00:00 +0100 1570472