9604561 Clark This proposal is on research to examine two key issues in the development of enzymes and other proteins from thermophilic microorganisms which are to: (1) develop processing methods to obtain significant quantities of these enzymes for further investigation and potential application, and (2) examine the mechanisms of pressure-induced stabilization of proteins from extreme thermophiles and devise approaches to manipulate the thermostability of these enzymes. Site-directed mutagenesis is to be used in a systematic way, along with biocatalytic studies at elevated pressures to elucidate the effects of pressure on protein thermostability and the interaction of subunits in these multimeric enzymes. ***