Preliminary screening of type IV secretion system in divergent geographic sources of .

In the present study, different geographical sources and sequence types (STs) of were preliminarily screened to investigate the distribution profiles of three core genes, VirB4, VirB6 and VirD4, of the type IV secretion system (T4SS). A total of 37 strains from different sources were screened, inoculated and prepared for genome extraction. toxins A and B were subjected to identification and multilocus sequence typing (MLST) analysis.