Hha controls Escherichia coli O157:H7 biofilm formation by differential regulation of global transcriptional regulators FlhDC and CsgD.

ABSTRACT: Although molecular mechanisms promoting adherence of enterohemorrhagic Escherichia coli (EHEC) O157:H7 on epithelial cells are well characterized, regulatory mechanisms controlling biofilm formation are not fully understood. In this study, we demonstrate that biofilm formation in EHEC O157:H7 strain 86-24 is highly repressed compared to that in an isogenic hha mutant. The hha mutant produced large quantities of biofilm compared to the wild-type strain at 30°C and 37°C. Complementation of the hha mutant reduced the level of biofilm formation to that of the wild-type strain, indicating that Hha is a negative regulator of biofilm production. While swimming motility and expression of the flagellar gene fliC were significantly reduced, the expression of csgA (encoding curlin of curli fimbriae)

SUBMITTER: Sharma VK 

PROVIDER: S-EPMC3623240 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature