|
V. G. Grigorenko, I. P. Andreeva, M. Yu. Rubtsova, V. V. Burmakin, I. V. Uporov, A. M. Egorov
Study
of catalytic properties of recombinant β-lactamases
TEM-1 and TEM-171 of molecular class A
Abstract
In this work preparation of recombinant β-lactamases
TEM-1 and TEM-171 of molecular class A, characterized by
a single amino acid substitutionof
valineatposition84to isoleucine(Val84Ile),
was studied. For the first time kinetic parameters for TEM-171
have been obtained with chromogenic substrate CENTA: KM eff= 23 µM, kcat=
102 s–1. Competitive type of β-lactamases
inhibition by tazobactam was ascertained. The inhibition constants for
tazobactam with CENTA as a substrate were as follows: 0.057 µM and 0.047 µM for
recombinant β-lactamase TEM-1 and TEM-171,
respectively. It was shown that Val84Ile substitution leads to a decrease of β-lactamase
TEM-171 thermostability by 1.5 times.
Key words: recombinant β-lactamase TEM-1, TEM-171, CENTA,
kinetic parameters, tazobactam, competitive type of inhibition.
Copyright (C) Chemistry Dept., Moscow State University, 2002
|
|
