Abstract：This study aimed to investigate the prevalence and MLST molecular typing of leukocytocidal gene subtypes in methicillin resistant Staphylococcus aureus (MRSA). A total of 287 MRSA strains were collected and divided into HA-MRSA and CA-MRSA. The pvl gene was amplified by PCR, and products were sequenced and analyzed for nucleotide variation. The pvl gene positive (pvl+) strains were genotyped by multi-site sequence typing (MLST), and the clone complex group (CC) was analyzed in eBURST software. A total of 51 strains were pvl+ strains (17.8%, 51/287), of which 29 strains were CA-MRSA (56.9%, 29/51) and 22 strains were HA-MRSA (43.1%, 22/51). Four loci (527,663, 1 396 and 1 729) were found to have nucleotide variations by two-way sequencing. According to the differences at 527 loci, which were divided into H (H1 and H2) and R (R1 and R2) subtypes, 46 strains (90.2%, 46/51) were H type (6 strains H1, 40 strains H2), and five strains (9.8%, 5/51) were R type (one strain R1, four strains R2). The H type strains mainly belonged to CC59 (ST59/ST388; 69.6%, 32/46), followed by CC22 (ST22; 10.9%, 5/46), CC1 (ST1/ST188; 6.5%, 3/46), CC88 (ST88; 4.3%, 2/46), CC5 (ST149; 4.3%, 2/46), CC9 (ST9; 2.2%, 1/46) and CC30 (ST30; 2.2%, 1/46). Type R was found only in strains CC59 (ST59), CC88 (ST88) and CC5 (ST25). The pvl carried by CA-MRSA and HA-MRSA was mainly subtype H, accounting for 86.2% (25/29) and 95.5% (21/22), respectively. No significant difference was observed between groups. The pvl carried by MRSA in this region was mainly H subtype (H2), The primary clone type was CC59. No significant difference in PVL subtypes carried by CA-MRSA and HA-MRSA was found.
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