Open Access -Lactamases from Yersinia enterocolitica
Author(s) -
G. Cornelis,
E. P. Abraham
Publication year - 1975
Publication title -
journal of general microbiology/journal of general microbiology
Language(s) - Uncategorized
Resource type - Journals
eISSN - 2059-9323
pISSN - 0022-1287
DOI - 10.1099/00221287-87-2-273
Subject(s) - cephaloridine , yersinia enterocolitica , cloxacillin , chemistry , enzyme , cephalosporin , beta lactamase , microbiology and biotechnology , strain (injury) , bacteria , cefalexin , hydrolysis , ampicillin , biochemistry , antibiotics , escherichia coli , biology , anatomy , genetics , gene
Two beta-lactamases, A and B, have been shown to be present in a strain of Yersinia enterocolitica (w222). Beta-Lactamase A hydrolyses a variety of penicillins and cephalosporins. This enzyme is sensitive to thiol reagents, is only partially inhibited by 0-1 mM-cloxacillin and has a molecular weight of approximatley 20,000.beta-Lactamase B shows strong cephalosporinase activity but does not hydrolyse some of the penicillins. It is more resistant than beta-lactamase A to thiol reagents, is completely inhibited by 0-1 mM-cloxacillin and has a molecular weight of about 34,000. With cephaloridine as a substrate, which is readily hydrolysed by both enzymes, about 85% of the total activity of a cell extract is due to beta-lactamase A and 15% to B. Addition of 6-aminopenicillanic acid to the culture during growth results in a 2-to4-fold selective increase in the amount of beta-lactamase B. Two beta-lactamases similar to enzymes A and B have been found in five other strains of Y. enterocolitica. In contrast, only one beta-lactamase, similar to enzyme B, has been detected in a different strain of Y. enterocolitica (H66), which is abnormal in that it is sensitive to ampicillin. Addition of 6-aminopenicillanic acid to cultures of this strain results in an 8-to 10-fold increase in beta-lactamase production.