Kinetic evidence for a two-step mechanism for the binding of chymotrypsin to alpha 1-proteinase inhibitor.

ABSTRACT: We have used the proflavin displacement method and a stopped-flow apparatus to measure the rate constant for the binding of 2 microM-chymotrypsin to 20-125 microM-alpha 1-proteinase inhibitor. The observed pseudo-first-order constant showed a hyperbolic dependence on alpha 1-proteinase inhibitor concentration, suggesting a reaction mechanism in which a fast pre-equilibrium (K = 0.19 mM) is followed by a first-order formation of the final complex (k = 252 s-1).

SUBMITTER: Bruch M 

PROVIDER: S-EPMC1138609 | biostudies-other | 1989 May

REPOSITORIES: biostudies-other