Distribution of beta-lactamases and phenotype analysis in clinical strains of Acinetobacter calcoaceticus.
One hundred clinical strains of Acinetobacter calcoaceticus isolated from 1981 to 1986 were screened for enzymatic resistance to beta-lactam antibiotics. Fourteen beta-lactam antibiotics were tested and four phenotypes were defined on the basis of enzymatic resistance and of susceptibility to the following beta-lactams: ticarcillin, piperacillin, cefotaxime, and ceftazidime. The resistance of A. calcoaceticus to beta-lactam antibiotics was predominantly due to beta-lactamases, which were produced by 81% of the strains. In most (71%) of the beta-lactamase producing strains, a penicillinase of the TEM type was observed; in 9% of the strains, all isolated since 1985, a CARB-type penicillinase with a pI 6.3 was observed. The presence of a cephalosporinase type enzyme was detected in acinetobacter strains isolated since 1981 and its incidence increased in 1986. Multiple beta-lactamases (penicillinase plus cephalosporinase) were observed in 32% of the strains.
Joly-Guillo
M L
ML
Department of Microbiology, Bichat University-Hospital, Paris, France.
Vallée
E
E
Bergogne-Bérézin
E
E
Philippon
A
A
D000150:Acinetobacter / Q000187:drug effects*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D007526:Isoelectric Point; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D001618:beta-Lactamases / Q000032:analysis*; D047090:beta-Lactams
D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases