Molecular Epidemiology and Horizontal Transfer Mechanism of -Carrying Linezolid-Resistant .

The aim of this work was to provide a theoretical and scientific basis for the treatment, prevention, and control of clinical drug-resistant bacterial infections by studying the molecular epidemiology and horizontal transfer mechanism of -carrying linezolid-resistant strains (LREfs) that were clinically isolated in a tertiary hospital in Kunming, China. Non-repetitive LREfs retained in a tertiary A hospital in Kunming, China. The strains were identified by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The transferability and horizontal transfer mechanism of gene were analyzed using polymerase chain reaction (PCR), whole-genome sequencing (WGS), and conjugation experiments. A total of 39 LREfs strains were collected, and all of them were multi-drug resistant. There were 30 LREfs strains (76.9%) carrying the gene, The genes and mutations in the 23S rRNA gene were not detected. The conjugation experiments showed that only three of 10 randomly selected -carrying LREfs were successfully conjugated with JH2-2. Further analysis of one successfully conjugated strain revealed that the gene, located in the donor bacterium, formed the transferable fragment under the mediation of the mobile genetic element (MGE) , which was then transferred to the recipient bacterium via horizontal plasmid transfer. Carrying the gene is the primary resistance mechanism of LREfs strains. The gene could carry the and genes to co-transfer among . MGEs such as insertion sequence play an important role in the horizontal transfer of the gene.