Comparison of two beta-lactamase-producing strains of Streptococcus faecalis.
AUTOR(ES)
Murray, B E
RESUMO
A second strain of enterococcus (PA) producing beta-lactamase (Bla+ phenotype) was compared with the previously reported Bla+ enterococcus, strain HH22. As with the original strain, there was a marked inoculum effect when PA was tested with penicillin, ampicillin, and piperacillin; no difference was noted with methicillin, cephalothin, imipenem, or vancomycin; the difference with ticarcillin was intermediate. High-level gentamicin resistance (Gmr) transferred from PA to an enterococcal recipient strain at a frequency approximately 100-fold lower than for HH22; all Gmr transconjugants from both strains were Bla+, but only PA showed linkage of Gmr and Bla+ with transfer of resistance to streptomycin, tetracycline, and chloramphenicol. EcoRI digestion of plasmid DNA from Gmr Bla+ transconjugants showed no similarities between the two strains. A 5.1-kilobase EcoRI Bla+-encoding fragment derived from HH22 was cloned into an Escherichia coli cloning vector and shown to hybridize to a 10.2-kilobase EcoRI fragment derived from PA; both fragments hybridized to an 840-base-pair staphylococcal Bla+ gene probe. These data indicate that the penicillinases are similar but encoded on different or differently arranged plasmids. The fact that both are transferable emphasizes the potential for this new streptococcal resistance determinant to disseminate.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=180608Documentos Relacionados
- Epidemiology of an endemic strain of beta-lactamase-producing Enterococcus faecalis.
- Sequence analysis of the beta-lactamase repressor from Staphylococcus aureus and hybridization studies with two beta-lactamase-producing isolates of Enterococcus faecalis.
- Beta-lactamase-producing enterococci.
- Antibiotic Susceptibility of Beta-Lactamase-Producing Strains of Branhamella (Neisseria) catarrhalis
- Molecular epidemiology of beta-lactamase-producing enterococci.