9305002 Biltonen A study of the activation of the phospholipase A2 from Agkistrodon piscivorus piscivorus will be undertaken utilizing site directed mutagenesis and a variety of biophysical techniques. It is hypothesized that dimerization is required for full activation of the interfacial enzyme. Multidimensional NMR, calorimetry, thermal denaturation, and fluorescence kinetic studies will be involved. %%% Major controversy surrounds the mechanism of interfacial catalysis by phospholipase A2s. These enzymes are involved in a wide variety of physiological responses. The studies planned here will test the hypothesis that the enzyme functions as a homodimer. DIrect physical characterization of the physical state of the enzyme will be used to answer this question. ***
