[Analysis of penicillin and ampicillin resistance in bacteria i. resistance and beta-lactamase production in clinical isolates (author's transl)].
The penicillin beta-lactamase (PBL) activity of the clinical isolates was measured at the same time by colorimetric microtitration, the iodometric method and chromatographic analysis. The minimal inhibitory concentration (MIC) of ampicillin (Ap) was determined for each isolate, the character of the coupled resistances, their frequency and distribution in the PBL producing and PBL-negative strains were also investigated. It was found that 1. the MIC value was 100 microgram/ml in 87.5 per cent of the Penicillin (P) and Ap resistant clinical isolates, 2. PBL was produced by 55--75 per cent of the P and Ap resistant strains depending on the species of the bacteria, 3. less than 50 per cent of the E. coli isolates produced PBL; in the case of other species this value was higher, about 65--70 per cent, 4. resistance to Su, SM, Tc, Nm and Cm was most frequently coupled to Ap and P resistance, 5. the distribution curve representing the number of the coupled resistance to the Ap and P shows a peak with 6 coupled antibiotics in the PBL-negative strains and 2 peaks in the PBL-producing strains.
D000667:Ampicillin / Q000494:pharmacology; D004926:Escherichia coli / Q000201:enzymology; D007709:Klebsiella / Q000201:enzymology; D010403:Penicillin Resistance; D010406:Penicillins / Q000494:pharmacology*; D011511:Proteus / Q000201:enzymology; D011549:Pseudomonas / Q000201:enzymology; D013210:Staphylococcus / Q000201:enzymology; D001618:beta-Lactamases / Q000378:metabolism*
D010406:Penicillins; D000667:Ampicillin; D001618:beta-Lactamases
Analyse der Penicillin- und Ampicillinresistenz von Bakterien I. Resistenz und beta-Laktamaseproduktion bei klinischen Isolaten.