TYPE-I BETA-LACTAMASES OF ENTEROBACTER-CLOACAE AND RESISTANCE TO BETA-LACTAM ANTIBIOTICS

The interaction of type-I beta-lactamases from Enterobacter cloacae wi th diverse beta-lactam compounds was examined. The ability of penicill in and cefoxitin to induce beta-lactamase production in this strain wa s assessed. The effect of beta-lactamase inhibitors was measured on be ta-lactamase extracts and on intact cells. E. cloacae 78 strain is a s tably derepressed mutant showing limited susceptibility to a number of antibiotics except imipenem. Imipenem would therefore be the appropri ate choice for therapy of infections caused by stably derepressed muta nts of Enterobacter sp. producing type-I beta-lactamases.