Identification of a novel insertion sequence in vanB2-containing Enterococcus faecium

The characterization of a novel insertion sequence (IS) in vanB2-containing Enterococcus faecium was conducted.

Direct PCR amplification of ORFC region of Tn5382 from DNA extracted from vanB2-containing E. faecium, and sequence analysis were performed. A novel IS was identified. It is 1418 bp in length and contains one putative open reading frame that is similar to transposase. There exists inverted terminal repeats of 12 bp, but direct repeats are not present. According to high similarity to putative transposases of IS3 members, such as, IS150, IS861, IS1077 and IS911, we designated it ISEnfa3.

Since ISEnfa3 was detected in all vanB2-containing strains examined so far, it could be used as a tool for epidemiological study.