Molecular typing of Shigella strains using PAGE in Fujian

Objective To study the molecular typing of Shigella in Fujian by pulsed field gel electrophoresis(PFGE),and to describe the epidemiological features of gene groups.Methods 96 strains of Shigella were isolated from patients and were analyzed by PAGE after digestion with Not I enzyme.H9812 was used as molecular weight marker and BioNumerics for cluster analysis.Results Based on 100% similarity,the finger printings of 34 Shigella flexneri and 62 Shigella sonnei were divided into 27 and 43 PFGE types.According to TENOVER principle,there were 2 dominant gene groups(G1-G2) of Shigella flexneri and 4 prevalent gene groups(GI-GIV) of Shigella sonnei.The dominant gene groups usually appeared from July to October,while other types could appear at any time without regional aggregation.Conclusions The diversity of molecular types of Shigella in Fujian is obvious,and some prevalent gene groups of Shigella flexneri and Shigella sonnei may gradually evolve to predominant and stable epidemic strains.