Linkage of erm(B) and aadE-sat4-aphA-3 in multiple-resistant Enterococcus faecium isolates of different ecological origins.
Enterococcus faecium shares its antibiotic resistance gene pool with various Gram-positive bacteria. A gene cluster aadE-sat4-aphA-3, which was first described in staphylococci, has been recently identified also in E. faecium. In staphylococci, this gene cluster was mostly integrated into the transposable element, Tn5405. We identified five different cluster types of Tn5405-like elements that were linked to erm(B) in 47 of 67 aadE-sat4-aphA-3 and erm(B) positive isolates (70.1%). Clusters differed by insertion of additional DNA between the IS1182 transposase gene and the left inverted repeat of IS1182, an integration of IS1216 between erm(B) and ORF X deleting IS1182 and the 5' end of ORF X, or a loss of the left end of Tn5405 including IS1182, ORF X, and the 5' end of ORF Y. Twenty isolates (29.8%) possessed neither a link between erm(B) and aadE-sat4-aphA-3 nor an arrangement of aadE-sat4-aphA-3 in a Tn5405-like element. A 17-kb composite cluster was identified in a single hospital isolate linking determinants for glycopeptide (vanA), macrolide-lincosamide-streptogramin B [erm(B)], and aminoglycoside-streptothricin (aadE-sat4-aphA-3) resistances.
Werner
Guido
G
Robert Koch Institute, Wernigerode Branch, D-38855 Wernigerode, Germany. wernerg@rki.de
Hildebrandt
Bianca
B
Witte
Wolfgang
W
D000617:Aminoglycosides / Q000494:pharmacology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D004251:DNA Transposable Elements; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D017753:Ecosystem; D016984:Enterococcus faecium / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D008780:Methyltransferases / Q000235:genetics* / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D005810:Multigene Family; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D013309:Streptothricins / Q000494:pharmacology
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D013309:Streptothricins; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase