Mechanism of horizontal transfer of linezolid resistance gene optrA media-ted by plasmids in Enterococcus faecalis
10.12138/j.issn.1671-9638.20256594
- VernacularTitle:质粒介导的利奈唑胺耐药基因optrA在粪肠球菌的水平转移机制
- Author:
Peini YANG
1
;
Li CHEN
1
;
Wei HE
1
;
Xiuwei ZHAI
1
;
Mei LYU
1
;
Qing WANG
1
;
Xu YANG
1
Author Information
1. 昆明医科大学第二附属医院检验科,云南 昆明 650032
- Publication Type:Journal Article
- Keywords:
Enterococcus faecalis;
linezolid;
plasmid;
optrA;
whole-genome sequencing;
horizontal transfer
- From:
Chinese Journal of Infection Control
2025;24(1):67-76
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the horizontal transfer mechanism of optrA gene-carrying linezolid-resistant En-terococcus faecalis(LREf)among clinical Enterococcus faecalis mediated by plasmids.Methods Non-repeated LREf from a tertiary first-class hospital in Kunming City from August 2022 to August 2023 were collected and iden-tified by matrix-assisted laser desorption/ionisation-time of flight mass spectrometry(MALDI-TOF MS).Antimi-crobial susceptibility testing was performed by VITEK 2 Compact,disc diffusion method and microbroth dilution method,optrA gene was detected by polymerase chain reaction(PCR),molecular biology characteristics of LREf was analyzed by whole-genome sequencing(WGS),LREf as the donor strain and clinically isolated Enterococcus faecalis as the recipient strain for conjugation test.Results A total of 17 LREf strains were collected,optrA gene was detected from plasmids of 12 LREf strains.Multiple resistance genes and virulence genes were detected.12 LREf strains were mainly ST16 type(50.0%).Among the 24 transconjugates in the conjugation test,8 were suc-cessfully conjugated,with a conjugation rate of 33.3%.Further analysis revealed that IS1216E insertion sequences presented at upstream and downstream of the optrA gene on the plasmid before and after conjugation of strains,and formed IS1216E-fexA-optrA-erm(A)-IS1216E-like transposon units.Conclusion The optrA gene can be horizon-tally transferred among clinical Enterococcus faecalis by mediating of plasmid of genes carrying both erm(A)and fexA,and the insertion sequence IS1216E plays an important role in its horizontal transfer process.