ToxR of Vibrio cholerae affects biofilm, rugosity and survival with Acanthamoeba castellanii

BMC Research Notes

Hadi Abd²  Gunnar Sandström²  Amir Saeed²  Sun N Wai¹  Soni P Valeru² 

[1] Department of Molecular Biology, Umeå University, 90187 Umeå, Sweden;Karolinska Institute, Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska University Hospital, Huddinge, SE-141 86, Stockholm, Sweden

关键词: Association with amoebae;    Biofilm;    Rugose colonies;    Outer membrane proteins;    V. cholerae;   

Others  :  1166776
DOI  :  10.1186/1756-0500-5-33

 received in 2011-08-17, accepted in 2012-01-16,  发布年份 2012

【 摘 要 】

Background

Vibrio cholerae causes the diarrheal disease cholera and utilizes different survival strategies in aquatic environments. V. cholerae can survive as free-living or in association with zooplankton and can build biofilm and rugose colonies. The bacterium expresses cholera toxin (CT) and toxin-coregulated pilus (TCP) as the main virulence factors. These factors are co-regulated by a transcriptional regulator ToxR, which modulates expression of outer membrane proteins (OmpU) and (OmpT). The aims of this study were to disclose the role of ToxR in expression of OmpU and OmpT, biofilm and rugose colony formation as well as in association with the free-living amoeba Acanthamoeba castellanii at different temperatures.

Results

The toxR mutant V. cholerae produced OmpT, significant biofilm and rugose colonies compared to the wild type that produced OmpU, decreased biofilm and did not form rugoes colonies at 30°C. Interestingly, neither the wild type nor toxR mutant strain could form rugose colonies in association with the amoebae. However, during the association with the amoebae it was observed that A. castellanii enhanced survival of V. cholerae wild type compared to toxR mutant strain at 37°C.

Conclusions

ToxR does seem to play some regulatory role in the OmpT/OmpU expression shift, the changes in biofilm, rugosity and survival with A. castellanii, suggesting a new role for this regulatory protein in the environments.

【 授权许可】

   
2012 Valeru et al; licensee BioMed Central Ltd.

【 图 表 】

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