BioIogicaI characteristics of vancomycin-dependent enterococcus faecium
HAN Qingzhen
XU Jie
ZHANG Xianfeng
QIAN Xuefeng
ZHANG Yang
SHI Jinfang
QIU Huiying
Abstract：Objective To observe the biological characteristics of a vancomycin-dependent enterococcus faecium (VDEfm-1501).Methods A strain of VDEfm-1501 was isolated from an urine specimen of a woman with blood system disease and was identified by VITEK 2,followed by PCR and VITEK MS.The VDEfm-1501 vancomycin-dependent growth characteristics and the minimum vancomycin concentration required for growth were tested by E-test.Its antibiotic resist-ance was analyzed by K-B disc diffusion.Drug resistance and virulence genes were amplified by PCR.The multilocus se-quence typing (MLST)was applied in the sequence typing.Ddl sequencing of VDEfm-1501 was detected by PCR.Results VDEfm-1501 could only grow on the presence of 1.0 μg/mL vancomycin at least,but such characteristic could weaken with the increase of passage times,and no vancomycin-dependence was found in the sixth passage.VDEfm-1501 showed multi-drug resistance except linezolid and tetracycline,and carried resistant gene of ace(6')-Ie-aph(2")-la.VDEfm-1501 belonged to clonal complex 17 (CC17),which was the cause of most of the nosocomial VRE outbreaks globally.And its vancomycin dependence seemed to be associated with the insertion of 'GG'at nucleotide position 942 of the ddl gene.Con-clusions The growth of VDEfm-1501 needs at least 1 μg/mL vancomycin,but such dependence is easy to lose.VDEfm-1501 displays multi-drug resistance and carrys the resistant gene of ace(6')-Ie-aph(2")-la.VDEfm-1501 belongs to ST of VRE.The insertion of 'GG'leads to the emergence of VDEfm-1501.
Keywords：enterococcusvancomycin-resistant enterococcivancomycin-dependent enterococcienterococcus faeci-umvancomycin-dependent enterococcus faeciumvancomycinteicoplanin
Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 26-29 )