The THIN-B metallo-beta-lactamase, a subclass B3 enzyme produced by the environmental species Janthinobacterium lividum, was overproduced in Escherichia coli by means of a T7-based expression system. The enzyme was purified (>95%) by two ion-exchange chromatography steps and subjected to biochemical analysis. The native THIN-B enzyme is a monomeric protein of 31 kDa. It exhibits the highest catalytic efficiencies with carbapenem substrates and cephalosporins, except for cephaloridine, which acts as a poor inactivator. Individual rate constants for inactivation by chelators were measured, suggesting that inactivation occurred by a mechanism involving formation of a ternary complex.
Biochemical Characterization of the THIN-B metallo-beta-Lactamase of Janthinobacterium lividum
PRENNA, Manuela;
2004-01-01
Abstract
The THIN-B metallo-beta-lactamase, a subclass B3 enzyme produced by the environmental species Janthinobacterium lividum, was overproduced in Escherichia coli by means of a T7-based expression system. The enzyme was purified (>95%) by two ion-exchange chromatography steps and subjected to biochemical analysis. The native THIN-B enzyme is a monomeric protein of 31 kDa. It exhibits the highest catalytic efficiencies with carbapenem substrates and cephalosporins, except for cephaloridine, which acts as a poor inactivator. Individual rate constants for inactivation by chelators were measured, suggesting that inactivation occurred by a mechanism involving formation of a ternary complex.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
