Stability and Functionality of Immobilized Proteins, Enzymes and Active-Site Analogues

摘要

Investigations of the functional properties of immobilized forms of heme proteins and organophosphate-degrading enzymes were undertaken. In these studies, cross-linking and immobilization procedures were used to control the local environment of the active sites of organophosphate-hydrolyzing enzymes, respiratory proteins, and active-site analogues. Data was obtained on the functional consequences of restrictions in conformational mobility. Although a number of basic findings on the functional consequences of immobilization were obtained with hemoglobin as a model protein, the organophosphate-degrading enzymes were used extensively in the second and third years of this contract. Highlights of results obtained are those related to long-term stability of immobilized organophosphate degrading enzymes. Cultures of Flavobacterium were established. Standard techniques of enzymology were utilized to quantify the extent of substrate specificity of the intact organism and of organophosphate-hydrolyzing enzymes isolated from this bacterium. It was determined that DFP as well as Parathion could be rapidly and repetitively hydrolyzed by the free and immobilized catalysts. Special emphasis was placed on enzyme reactivity and stability under conditions of limited water availability. Keywords: Cytochrome Oxidase, Biotechnology.