A genomic island integrated into recA of Vibrio cholerae contains a divergent recA and provides multi-pathway protection from DNA damage

作者：Rapa Rita A; Islam Atiqul; Monahan Leigh G; Mutreja Ankur; Thomson Nicholas; Charles Ian G; Stokes Harold W; Labbate Maurizio^*

来源：Environmental Microbiology, 2015, 17(4): 1090-1102.

DOI：10.1111/1462-2920.12512

Lateral gene transfer (LGT) has been crucial in the evolution of the cholera pathogen, Vibrio cholerae. The two major virulence factors are present on two different mobile genetic elements, a bacteriophage containing the cholera toxin genes and a genomic island (GI) containing the intestinal adhesin genes. Non-toxigenic V.cholerae in the aquatic environment are a major source of novel DNA that allows the pathogen to morph via LGT. In this study, we report a novel GI from a non-toxigenic V.cholerae strain containing multiple genes involved in DNA repair including the recombination repair gene recA that is 23% divergent from the indigenous recA and genes involved in the translesion synthesis pathway. This is the first report of a GI containing the critical gene recA and the first report of a GI that targets insertion into a specific site within recA. We show that possession of the island in Escherichia coli is protective against DNA damage induced by UV-irradiation and DNA targeting antibiotics. This study highlights the importance of genetic elements such as GIs in the evolution of V.cholerae and emphasizes the importance of environmental strains as a source of novel DNA that can influence the pathogenicity of toxigenic strains.

• 出版日期2015-4