Identification of the gene mutation conferring resistance to linezolid in a strain of Enterococcus faecalis

Objective To investigate the mechanism of linezolid resistance in a strain of Enterococcus faecalis. Methods We isolated a linezolid-resistant Enterococcus faecalis from the sputum in a patient with heamtological disease. The 23S rRNA V-region and 4 copies of 23S rRNA gene fragments of the linezolid-resistant Enterococcus faecalis strain were amplified using polymerase chain reaction (PCR), followed by DNA sequencing and sequence alignment analysis. Results One G→U mutation at the 2576 nucleotide (G2576U) was identified in the V-region of 23S rRNA of this drug-resistant strain. A G2576U mutation was also found in three out of the four copies of gene fragments of 23S rRNA. Conclusions G2576U point mutation may be the cause of resistance of this strain to linezolid.