pep(27) and lytA in Vancomycin-Tolerant Pneumococci
Por:
Olivares A., Trejo J.O., Arellano-Galindo J., Zuniga, G, Escalona G., Vigueras J.C., Marín P., Xicohtencatl J., Valencia P., Velázquez-Guadarrama N.
Publicada:
1 dic 2011
Resumen:
Vancomycin therapy failure due to the emergence of tolerance in pneumococci is increasing. The molecular mechanism of tolerance is not clear, but lytA and pep(27) are known to be involved. Our aim was to evaluate the expression of both genes in vancomycin-tolerant Streptococcus pneumoniue (VTSP) strains. Eleven VTSP strains from a total of 309 clinical isolates of S. pneutnoniue from 1997 to 2006 were classified according to the criteria of Liu and Tomasz. All VTSP strains were evaluated for susceptibility according to CLSI criteria, serotype by the Quellung test, and clonality by PFGE. The expressions of lytA and pep(27) were analyzed in different growth phases by RT-PCR with and without vancomycin. Eighty-two percent of VTSP strains showed resistance to penicillin, and 100% were sensitive to vancomycin and cefotaxime. The most frequent serotypes of VTSP strains were 23F (4/11) and 6B (3/11). Clonal relationship was observed in only two strains. No significant changes were observed in
Filiaciones:
Olivares A.:
Autonomous Univ Mexico City, Genom Sci Dept, San Lorenzo 290, Mexico
Trejo J.O.:
Autonomous Univ Mexico City, Genom Sci Dept, San Lorenzo 290, Mexico
Arellano-Galindo J.:
Bacteriology Laboratory, Federico Gómez Children's Hospital of México, Dr. Marquez 162, Mexico
Escalona G.:
Bacteriology Laboratory, Federico Gómez Children's Hospital of México, Dr. Marquez 162, Mexico
Vigueras J.C.:
Bacteriology Laboratory, Federico Gómez Children's Hospital of México, Dr. Marquez 162, Mexico
Marín P.:
Bacteriology Laboratory, Federico Gómez Children's Hospital of México, Dr. Marquez 162, Mexico
National School of Biological Science, National Polytechnic Institute, Plan de Ayala S/N, Mexico
Xicohtencatl J.:
Bacteriology Laboratory, Federico Gómez Children's Hospital of México, Dr. Marquez 162, Mexico
Valencia P.:
Bacteriology Laboratory, Federico Gómez Children's Hospital of México, Dr. Marquez 162, Mexico
Velázquez-Guadarrama N.:
Bacteriology Laboratory, Federico Gómez Children's Hospital of México, Dr. Marquez 162, Mexico
|