This award in the Inorganic, Bioinorganic and Organometallic Chemistry Program will support continued studies by Professor R. H. Holm of Harvard University in several areas of bioinorganic chemistry. Areas to be investigated include 1) molybdenum oxotransferases including synthesis of analogues and isotopic labeling studies of rabbit liver aldehyde oxidase; 2) synthesis of models for the cofactors of nitrogenase; 3) functional models of the nickel enzymes hydrogenase and CO dehydrogenase. In all analogue studies emphasis is on synthetic models that provide functional mimics of the enzyme action. In a less biologically related area investigations of the synthesis of molecular chalogenide clusters from soluble thiometallates and by excision of fragments from insoluble, nonmolecular solids will be undertaken. %%% The nature of many enzymes is such that precise molecular structures and mechanistic details cannot be determined by conventional physical techniques. A variety of indirect methods have evolved that can be used to infer enzyme structures and to help define the individual chemical steps involved in their catalytic mechanisms. The application and development of these indirect methods is the purpose of this research.
