Influence of iron-chelated growth conditions on outer membrane protein production and virulence of Vibrio tubiashii.

Growth of two Vibrio tubiashii strains under iron-chelated conditions resulted in the production of a hydroxymate-like siderophore, and expression of outer membrane proteins with homologies to proteins in Vibrio cholerae and Vibrio vulnificus which were not seen in cells grown under non-chelated growth conditions. PCR analysis using primers based on Listonella anguillarum's ferric uptake Repressor protein (fur) gene detected a 316 bp fur gene homolog which also had sequence homology to the fur genes of V. cholerae and V. vulnificus. V. tubiashii cultured under iron-chelated growth conditions induced a greater fluid accumulation (FA) response in suckling mice than cells which were cultured under iron non-chelated growth conditions. Our observations that V. tubiashii possesses a fur-like gene homolog and expresses unique OMPs, a hydroxymate-like siderophore, and produces an increased fluid accumulation response in suckling mice when grown under iron-chelated condition support previous findings that V. tubiashii may have the essential components for the survival and establishment of infections and this report represents the first observations of competent iron acquisition system in V. tubiashii which is similar to those produced by other marine vibrios, many of which are pathogenic for humans.