RESUMEN
The affinities of six major penicillin-binding proteins (PBPs) of Yersinia pestis EV76 to different beta-lactam antibiotics were determined. The results indicate that, similar to their counterparts in Escherichia coli, PBP2 and PBP3 are the lethal targets of amdinocillin and furazlocillin, respectively. The PBP contents of four additional Y. pestis strains and the morphological effects produced by some beta-lactam antibiotics are also reported.
Asunto(s)
Antibacterianos/metabolismo , Proteínas Bacterianas , Proteínas Portadoras/metabolismo , Hexosiltransferasas , Muramoilpentapéptido Carboxipeptidasa/metabolismo , Peptidil Transferasas , Yersinia pestis/metabolismo , Antibacterianos/farmacología , Proteínas Portadoras/química , Muramoilpentapéptido Carboxipeptidasa/química , Proteínas de Unión a las Penicilinas , Unión Proteica , Yersinia pestis/efectos de los fármacos , Yersinia pestis/ultraestructura , beta-LactamasRESUMEN
Six major bands corresponding to penicillin-binding proteins (PBPs) with molecular weights ranging from 43,000 to 97,000 were detected in cell envelopes of Yersinia pestis EV76 grown at 28 degrees C. When cells were transferred to 37 degrees C and incubated for extended periods of time, the amounts of all PBPs, except for PBP2, were gradually reduced in cell envelopes of a strain carrying a 75-kb virulence-associated plasmid (as measured by penicillin-binding capacity), whereas in a strain cured of the plasmid, all PBPs were stable. The results indicated that the stability and/or the expression of Y. pestis PBPs is affected by a temperature-inducible pathway associated with the virulence-associated plasmid.