First Report Cfr and OptrA Co-harboring Linezolid-Resistant Enterococcus faecalis in China

A linezolid-resistant E.faecalis strain harboring optrA and cfr resistance genes were isolated from a patient in china, which had no mutations in rplC, rplD, rplV, and 23S rRNA gene. Transformation indicated that optrA and cfr were located on two different plasmids and both could be transferred to recipient strain, resulting in the increase of MICs of linezolid and chloramphenicol. Cfr, carried by an 11,872-bp plasmid, was enclosed with an IS110 transposase in upstream and an IS3-like transposase in downstream, while optrA was on an 8357-bp plasmid. As far as we know, this is the first report of an E.faecalis clinical strain co-harboring optrA and cfr in China.