ABSTRACT
The characteristics of an unusual clinical isolate of Enterococcus faecium (CL-6729) showing insertion of IS19 (also known as ISEfm1) in the vanS gene while maintaining a constitutive VanA phenotype are described. This isolate was obtained from a hospital-acquired urinary tract infection, showed multidrug resistance by antimicrobial susceptibility testing, and belongs to ST78 based on multilocus sequence typing (MLST). Except for the vanS gene, all the other genes of the vanA gene cluster were intact according to conventional PCR, overlapping PCR and genome sequencing. By quantitative reverse transcription PCR (RT-qPCR), the isolate showed similar expression of the vanA, vanR and vanS genes in the presence and absence of vancomycin. The results suggest that insertion of IS19 in the vanS gene may be associated with constitutive expression of resistance to vancomycin in clinical isolate CL-6729, either by not impairing VanS activity or by inducing the emergence of another pathway that acts on vanA expression, which still needs to be fully investigated.
Subject(s)
Bacterial Proteins/genetics , Enterococcus faecium/drug effects , Enterococcus faecium/genetics , Mutagenesis, Insertional/genetics , Protein Kinases/genetics , Transcription Factors/genetics , Vancomycin Resistance/genetics , DNA Transposable Elements/genetics , Drug Resistance, Multiple, Bacterial/genetics , Enterococcus faecium/isolation & purification , Gram-Positive Bacterial Infections/drug therapy , Humans , Microbial Sensitivity Tests , Urinary Tract Infections/drug therapy , Urinary Tract Infections/microbiology , Vancomycin/pharmacologyABSTRACT
Here, we present the draft genome sequence of an unusual Enterococcus faecium isolate (CL-6729) showing constitutive expression of the VanA type of vancomycin resistance. The isolate was recovered from a patient with a nosocomial urinary tract infection in Brazil.
