CONFORMATIONAL ENERGY CALCULATIONS OF ENZYME‐SUBSTRATE INTERACTIONS. I. Computation of Preferred Conformations of Some Substrates of α‐Chymotrypsin

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.

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