Conformational energy calculations of enzyme-substrate interactions. I. Computation of preferred conformations of some substrates of -chymotrypsin.

Abstract

Empirical energy calculations are used to determine all low‐energy conformations of the isolated α‐chymotrypsin substrates N‐acetyl‐L‐phenylalanine amide, N‐acetyl‐L‐tyrosine amide, N‐formyl‐L‐tyrosine amide, and N‐acetyl‐L‐tryptophan amide. The computed conformations are in agreement with the available experimental data for L‐phenylalanyl, L‐tyrosyl and L‐tryptophanyl side chains in proteins, and with NMR and X‐ray data for these side chains in small peptides. In the following papers, certain of these low‐energy substrate conformations will be shown to bind selectively to the enzyme chymotrypsin to form stable noncovalent enzyme‐substrate complexes.