Siderophore production and outer membrane proteins of selectedVibrio vulnificusstrains under conditions of iron limitation

Possible iron-transport mechanisms were examined for 11 Vibrio vulnificus strains from clinical and environmental sources. All strains produced hydroxamate siderophores, and 10 of 11 produced phenolate siderophores. Each strain produced at least 2 new major outer membrane proteins in response to iron limitation; however, the apparent Mr of these proteins varied between strains. While certain patterns of major iron-regulated outer membrane proteins were more common among clinical strains, there was no clear correlation between outer membrane protein profile and source of the isolate. Immune serum showed a strong antigenic response to a 66-kD outer membrane protein that was common to all strains examined and was not iron-regulated. An antigenic response to other outer membrane proteins that appear to be iron-regulated was also noted.