Characterization of the S'-subsite specificity of V8 proteinase via acyl transfer to added nucleophiles

The S'-subsite specificity of endoproteinase Glu-C (V8 proteinase) was studied by acyl transfer reactions using Z-Glu-OMe as acyl donor and a series of amino acid- and peptide-derived nucleophiles. The partition constant, which characterizes specificity, was determined by a method based on the integrated rate equation. V8 proteinase prefers amino acid residues with hydrophobic side chains in the P'1 position. Di- and tripeptide amides are more efficient nucleophilic amino components than amino acid amides.