|
Bioorganometallic chemistry is the study of biologically active molecules that contain carbon directly bonded to metals or metalloids. This area straddles the fields of organometallic chemistry, biochemistry, and medicine. It is subset of bioinorganic chemistry. Naturally occurring bioorganometallics include enzymes and sensor proteins. Also within this realm is the development of new drugs and imaging agents as well as the principles relevant to the toxicology or organometallic compounds.〔Synthetic Models for Bioorganometallic Reaction Centers, G. Jaouen; Wiley-VCH: Weinheim, 2005.〕 ==Naturally occurring bioorganometallic species== Vitamin B12 is the preeminent bioorganometallic species. B12 is shorthand for a collection of related enzymes which effect numerous reactions involving the making and breaking of C-C and C-H bonds. Several bioorganometallic enzymes carry out reactions involving carbon monoxide. Carbon monoxide dehydrogenase (CODH) catalyzes the water gas shift reaction which provides CO for the biosynthesis of acetylcoenzyme A. The latter step is effected by the Ni-Fe enzyme acetylCoA synthase. ACS”. CODH and ACS often occur together in a tetrameric complex, the CO being transported via a tunnel and the methyl group being provided by methyl cobalamin. Hydrogenases are bioorganometallic in the sense that their active sites feature Fe-CO functionalities, although the CO ligands are only spectators.〔Cammack, R.; Frey, M. and Robson, R., Hydrogen as a Fuel: Learning from Nature, Taylor & Francis: London, 2001.〕 The Fe-only hydrogenases have a Fe2(μ-SR)2(μ-CO)(CO)2(CN)2 active site connected to a 4Fe4S cluster cluster via a bridging thiolate. The active site of the ()-hydrogenases are described as (NC)2(OC)Fe(μ-SR)2Ni(SR)2 (where SR is cysteinyl).〔Volbeda, A. and Fontecilla-Camps, J. C., "The Active Site and Catalytic Mechanism of NiFe Hydrogenases", Dalton Transactions, 2003, 4030-4038.〕 The “FeS-free” hydrogenases have an undetermined active site containing an Fe(CO)2 center. Methanogenesis, the biosynthesis of methane, entails as its final step, the scission of a nickel-methyl bond in cofactor F430. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Bioorganometallic chemistry」の詳細全文を読む スポンサード リンク
|