Kinetic study of the pseudolysin-catalyzed synthesis of Z-Ala-Phe-NH2

In recent years, enzymatic peptide synthesis, including synthesis of bioactive peptides and analogues, semi-synthetic proteins and bioactive peptides from recombinant precursors has been attracting increasing attention (for a review see [1, 2]). Pseudomonas aeruginosa elastase (pseudolysin), a thermolysin-like metalloproteinase has been shown to synthesize N-protected dipeptide amides with good yields and purities [3,4]. While both enzymes show some structural similarities [5] elastase but not thermolysin can incorporate tyrosine and tryptophane in P'1 position with high synthesis rates (S. Rival unpublished). Kinetic mechanisms of peptide synthesis by thermolysin have been already proposed [6–8]. In this work, mainly from conductimetric measurement of initial rates, we have studied the enzymatic mechanism of the pseudolysincatalyzed synthesis of Z-Ala–Phe–NH2 and the influence of some parameters.