Molecular characterization of Enterococcus faecium isolated from hospitalized patients in Korea.
OBJECTIVE
Multilocus sequence typing (MLST) was performed for vancomycin-resistant Enterococcus faecium (VREF) from diverse geographical areas in Korea to obtain insights into the genetic relationships with other molecular profiles. To understand the diversity of lineages, vancomycin-susceptible E. faecium (VSEF) were included.


RESULTS
A total of 60 E. faecium isolates were analysed by MLST and esp profile. Molecular typing of Tn1546 of 30 VREF strains was evaluated by overlapping PCR of Tn1546 and DNA sequencing. Seven sequence types (ST) were found among 30 VSEF isolates, and four STs were found among 30 VREF isolates. The types most frequently encountered were ST 78 (26 isolates) and ST 203 (16 isolates). Of the 60 E. faecium isolates, 35 isolates were positive for the esp gene. On molecular typing of Tn1546, all VREF isolates were divided into four main types. Strains with the same ST showed divergence in Tn1546 types and strains with the same Tn1546 type represented different STs.


CONCLUSIONS
An association between Tn1546 typing and MLST was not found.


CONCLUSIONS
These results suggest that the horizontal spread of Tn1546 between strains plays a major role in the dissemination of vancomycin resistance in Korea.
Lee
W G
WG
Department of Laboratory Medicine, Ajou University School of Medicine, Suwon, Korea. weegyo@ajou.ac.kr
Lee
S M
SM
Kim
Y S
YS
D015373:Bacterial Typing Techniques; D004251:DNA Transposable Elements / Q000235:genetics; D016984:Enterococcus faecium / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006761:Hospitals; D006801:Humans; D007723:Korea; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D020161:Physical Chromosome Mapping; D017422:Sequence Analysis, DNA; D020713:Vancomycin Resistance / Q000235:genetics*
D004251:DNA Transposable Elements