Distribution of genes encoding resistance to streptogramin A and related compounds among staphylococci resistant to these antibiotics.
AUTOR(ES)
Allignet, J
RESUMO
The levels of resistance to pristinamycin (Pt) and to its major constituents, pristinamycin IIA and IB (PIIA and PIB, respectively; classified as streptogramins A and B, respectively) were determined for 126 staphylococcal isolates. The results suggest tentative susceptibility breakpoints of < or = 2, < or = 8, and < or = 0.5 microgram/ml for PIIA, PIB, and Pt, respectively. Fifty-six isolates that were inhibited by > or = 4 micrograms of PIIA per ml were investigated for the presence of staphylococcal genes encoding resistance to PIIA (vga, vat, and vatB) and PIB (vgb). None of these genes was found in the 4 isolates inhibited by 4 micrograms of PIIA per ml or in 4 of the other 52 isolates tested. The remaining 48 isolates harbored plasmids carrying vatB and vga or combinations of genes (vga-vat-vgb or vga-vat). The absence of any known PIIA resistance gene from the four Staphylococcus aureus isolates inhibited by > or = 8 micrograms of PIIA per ml suggests that there is at least one PIIA resistance mechanism in staphylococci that has not yet been characterized.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=163568Documentos Relacionados
- Distribution of Genes Encoding Resistance to Macrolides, Lincosamides, and Streptogramins among Staphylococci
- Expression in Escherichia coli of a staphylococcal gene for resistance to macrolide, lincosamide, and streptogramin type B antibiotics.
- Molecular Analysis of Resistance to Streptogramin A Compounds Conferred by the Vga Proteins of Staphylococci
- Characterization of a Variant of vga(A) Conferring Resistance to Streptogramin A and Related Compounds
- Distribution of erm genes and low prevalence of inducible resistance to clindamycin among staphylococci isolates