|
Refinement of the structure of gamma-chymotrypsin based on X-ray
crystallographic data to 1.6-A resolution has confirmed the overall conformation
of the molecule as reported previously [Cohen, G. H., Silverton, E. W., &
Davies, D. R. (1981) J. Mol. Biol. 148, 449-479]. In addition, the new
refinement suggests that gamma-chymotrypsin, which is operationally defined by
its crystalline habit, may not be the free enzyme but rather a complex, possibly
an acyl-enzyme adduct, with the tetrapeptide Pro-Gly-Ala-Tyr (or a close
homologue). The crystallographic refinement provides a detailed geometrical
description of the enzyme-substrate-solvent interactions that occur in the
presumptive adduct.
|
