Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1969 Apr;62(4):1116-20.
doi: 10.1073/pnas.62.4.1116.

On the mechanism of pepsin action

T R Hollands, J S Fruton

On the mechanism of pepsin action

T R Hollands et al. Proc Natl Acad Sci U S A. 1969 Apr.

Abstract

The problem of the mechanism of pepsin action is considered in relation to recent data on the kinetics and specificity of the enzyme, as well as the finding, reported here, that pepsin exhibits a deuterium isotope effect in the cleavage of a peptide bond. The kinetic parameters for the hydrolysis of the Phe(NO(2))-Phe bond of Gly-Gly-Gly-Phe(NO(2))-Phe-OMe by pepsin have been determined in H(2)O and in D(2)O. The finding of a significant deuterium isotope effect (k(H2O)/k(D2O) = ca. 2) supports the hypothesis that the catalytic mechanism of pepsin involves the participation, in the rate-limiting step, of a proton donor (probably an enzymic carboxyl group) in addition to an enzymic carboxylate group acting as a nucleophile.

PubMed Disclaimer

References

    1. J Biol Chem. 1965 Aug;240:PC3447-8 - PubMed
    1. Biochim Biophys Acta. 1963 Jan 8;67:104-37 - PubMed
    1. Biochem Biophys Res Commun. 1966 May 3;23(3):243-5 - PubMed
    1. Biochem J. 1959 Sep;73:33-41 - PubMed
    1. Proc Natl Acad Sci U S A. 1967 Dec;58(6):2451-4 - PubMed

LinkOut - more resources