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
. 1988 Oct 1;255(1):119-22.
doi: 10.1042/bj2550119.

A survey of the kinetic parameters of class C beta-lactamases. Penicillins

M Galleni  1 , J M Frère
Affiliations

A survey of the kinetic parameters of class C beta-lactamases. Penicillins

M Galleni et al. Biochem J. .

Abstract

The interaction between six class C beta-lactamases and various penicillins has been studied. All the enzymes behaved in a very uniform manner. Benzylpenicillin exhibited relatively low kcat. values (14-75 s-1) but low values of Km resulted in high catalytic efficiencies [kcat./Km = 10 X 10(6)-75 X 10(6) M-1.s-1]. The kcat. values for ampicillin were 10-100-fold lower. Carbenicillin, oxacillin cloxacillin and methicillin were very poor substrates, exhibiting kcat. values between 1 x 10(-3) and 0.1 s-1. The Km values were correspondingly small. It could safely be hypothesized that, with all the tested substrates, deacylation was rate-limiting, resulting in acyl-enzyme accumulation.

PubMed Disclaimer

References

    1. Adv Microb Physiol. 1973;9:31-88 - PubMed
    1. Biochem J. 1988 Oct 1;255(1):123-9 - PubMed
    1. J Gen Microbiol. 1980 Dec;121(2):449-56 - PubMed
    1. Proc Natl Acad Sci U S A. 1981 Aug;78(8):4897-901 - PubMed
    1. Biochem J. 1982 Mar 1;201(3):621-7 - PubMed

Publication types