CHARGE STATE OF HIS 57-ASP 102 COUPLE IN β-TRYPSIN : A MOLECULAR ORBITAL STUDY

Abstract

The charge state of the His 57-Asp 102 couple in β-trypsin in the acid pH range was studied using the ab initio molecular orbital method. The result was in agreement with the NMR experiments which do not support the charge relay hypothesis proposed by Blow et al. It is remarkable that the charge state of His 57-Asp 102 couple is greatly affected by the environment around the catalytic triad.