Structural and thermodynamic analysis of the binding of solvent at internal sites in T4 lysozyme.

ABSTRACT: To investigate the structural and thermodynamic basis of the binding of solvent at internal sites within proteins a number of mutations were constructed in T4 lysozyme. Some of these were designed to introduce new solvent-binding sites. Others were intended to displace solvent from preexisting sites. In one case Val-149 was replaced with alanine, serine, cysteine, threonine, isoleucine, and glycine. Crystallographic analysis shows that, with the exception of isoleucine, each of these substitutions results in the binding of solvent at a polar site that is sterically blocked in the wild-type enzyme. Mutations designed to perturb or displace a solvent molecule present in the native enzyme included the replacement of Thr-152 with alanine, serine, cysteine, valine, and isoleucine. Although the

SUBMITTER: Xu J 

PROVIDER: S-EPMC2374199 | biostudies-literature | 2001 May

REPOSITORIES: biostudies-literature