Homodimerization and binding of specific domains to the target DNA are essential requirements for HlyU to regulate expression of the virulence gene rtxA1, encoding the repeat-in-toxin protein in the human pathogen Vibrio vulnificus.

ABSTRACT: The virulence gene rtxA1, encoding the repeat-in-toxin protein, plays an essential role in the pathogenesis of Vibrio vulnificus infections. Expression of this gene is controlled by the HlyU regulator by direct contact of the DNA upstream of the rtxA1 toxin operon acting as a derepressor of the H-NS protein. The crystal structure suggests that HlyU forms a homodimer in vitro. However, knowledge of the biological implications of these findings in vivo is limited. In this work, we endeavored to dissect, using genetic and biochemical approaches, the domains of this protein that are essential for homodimer formation and the interaction of HlyU with the target DNA. We identified that residues L18, N22, R25, S54, Q55, L57, W59, R61, K70, and Y77 are essential for the HlyU protein binding to the

SUBMITTER: Liu M 

PROVIDER: S-EPMC3232850 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature