Penicillinases of Klebsiella pneumoniae and their phylogenetic relationship to penicillinases mediated by R factors.
On the assumption that the penicillinase determinants on a group of R factors conferring ampicillin resistance have a phylogenetically close relationship to the penicillinase gene of the Klebsiella group, the penicillinases from four strains of K. pneumoniae, GN69, GN1103R(-), GN422, and GN118, were purified 230- to 1,000-fold and compared with the known two R-factor-mediated penicillinases. By gel filtration on Sephadex G-75, the molecular weights were estimated to be 17,400, 18,100, 20,000 and 18,300, respectively, which are slightly lower than those of the R-factor penicillinases. The isoelectric points of the Klebsiella penicillinases were not in agreement with those of the R-factor penicillinases. All the enzymes showed a pH optimum between 6.3 to 7.2 and a temperature optimum of 45 C, and those properties, together with behavior towards inhibitors, were about the same as those in the R-factor penicillinases. The substrate specificity and the Michaelis constants of the Klebsiella penicillinases for penicillins and cephaloridine were broadly similar to those of the R-factor penicillinases, however, some variations were found even among the four penicillinases of K. pneumoniae. The reactivities of the four penicillinases of K. pneumoniae with the antiserum against one R-factor penicillinase were tested, and three of the four Klebsiella penicillinases were found to be indistinguishable immunologically from both R-factor penicillinases. The remaining Klebsiella penicillinase, from GN1103R(-), showed an immunological partial homology with the R-factor penicillinases.
D000667:Ampicillin / Q000494:pharmacology; D005075:Biological Evolution; D002509:Cephaloridine / Q000494:pharmacology; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D004351:Drug Resistance; D004589:Electrophoresis, Disc; D006863:Hydrogen-Ion Concentration; D005779:Immunodiffusion; D007525:Isoelectric Focusing; D007709:Klebsiella / Q000201:enzymology*; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology; D008970:Molecular Weight; D009154:Mutation; D010400:Penicillin G / Q000494:pharmacology; D010404:Penicillin V / Q000031:analogs & derivatives / Q000494:pharmacology; D010405:Penicillinase / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism; D010406:Penicillins / Q000494:pharmacology; D013696:Temperature
D010406:Penicillins; D000667:Ampicillin; D010405:Penicillinase; D002509:Cephaloridine; D010400:Penicillin G; D010404:Penicillin V