Effects of drug binding on the esterase-like activity of human serum albumin. VI. Reaction with di-p-nitrophenyl adipate.

Publisher Website
Google Scholar
Abstract
The binding of R type drugs, which have high affinity to a site (R site) near the tyrosine-411 residue, remarkably accelerated the reaction of di-p-nitrophenyl adipate (D) with human serum albumin (HSA). The reaction was investigated kinetically at various pHs and 25.degree. C. The reaction in the presence of an excess of HSA over D proceeded in two steps. The pH-profiles for both rate constants were sigmoidal, indicating the participation of two tyrosine residues having pKa values of about 9.3 in the reactions. The two residues of HSA involved seem to be separated by a distance corresponding to the length of the adipoyl group.