ISSN:
1574-6968
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
Two novel β-lactamases conferring multiresistance to antibiotics including oxyimino β-lactams have been identified in two nosocomial K. pneumoniae strains isolated in Tunis in 1986 and 1988. Both enzymes were encoded by ca. 150-kilobase plasmids. Donor and transconjugant strains producing these enzymes exhibited highly similar pattern of resistance (CTX phenotype) to β-lactams including penicillins and oxyimino β-lactams e.g. cefotaxime, ceftriaxone, ceftazidime, and aztreonam. High and variable synergy (16 to 1066-fold) was obtained when combined to 0.1 μg/ml of clavulance (β-lactamase inhibitor). The isoelectric points of these two enzymes were 5.4 and 6.4. These β-lactamases differed from TEM types by hydrolysis for cefotaxime or ceftriaxone but were inhibited by clavulanate and cloxacillin. DNA hybridization studies suggested that the genes of these enzymes may be derived from genes encoding TEM-type enzymes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1574-6968.1990.tb13831.x