Iron uptake system medicated by Vibrio anguillarum plasmid pJM1

Abstract

Plasmid pJM1 from an invasive strain of V. anguillarum mediates an Fe-sequestering system that is associated with its ability to cause septicemia in marine fishes. This plasmid-mediated Fe uptake system was analyzed by using mutations caused by transposon Tn1. Restriction endonuclease analysis of Fe uptake-deficient and -proficient derivatives generated by insertion of Tn1 and molecular cloning experiments permitted localization of the plasmid regions involved in the process of Fe sequestration to a stretch of .apprx. 20 kilobase pairs. The existence of 2 plasmid-mediated components involved in Fe uptake in V. anguillarum was defined: a diffusible substance which functions as a siderophore and a nondiffusible receptor for Fe siderophore complexes, tentatively identified as the pJM1 plasmid-mediated outer membrane protien OM2 of V. anguillarum.