title: Manganese is an additional cation that enhances colonial phase variation of Vibrio vulnificus.
abstract: Vibrio vulnificus, an inhabitant of marine and estuarine environments around the world, is the leading cause of reported seafood-related deaths in the United States. Disease is caused by opaque colony-forming strains that produce capsular polysaccharide, loss of which results in an unencapsulated translucent phenotype with diminished virulence potential. Rugose is a third phenotypic variant of V. vulnificus, and produces a separate exopolysaccharide that results in a dry, wrinkled appearance and the ability to form profuse biofilms. Phase variation among these three phenotypes is influenced by several environmental factors, including the presence of calcium in the medium (Garrison-Schilling et al.). In this study, we have identified a second cation, manganese, which substantially increases the propensity of opaque V. vulnificus strains to switch to translucent or rugose phenotypes. In comparative studies, manganese and calcium promoted switching to the same phenotype for some strains but to different phenotypes for others, results of which indicate that the two cations do not always promote the same changes in underlying gene expression. The data here provide further evidence that exposure of V. vulnificus to select cations results in phenotypic changes that impact both virulence capacity and ecology of the organism.
authors.affiliation: Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA, 70803, USA.
authors.forename: Zelam M
authors.initials: ZM
authors.lastname: Kaluskar
authors.affiliation: Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA, 70803, USA.
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Garrison-Schilling
authors.affiliation: Department of Experimental Statistics, Louisiana State University, 171 Martin D. Woodin Hall, Baton Rouge, LA, 70803, USA.
authors.forename: Kevin S
authors.initials: KS
authors.lastname: McCarter
authors.affiliation: Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA, 70803, USA.
authors.forename: Bliss
authors.initials: B
authors.lastname: Lambert
authors.affiliation: Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA, 70803, USA.
authors.forename: Shelby R
authors.initials: SR
authors.lastname: Simar
authors.affiliation: Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA, 70803, USA.
authors.forename: Gregg S
authors.initials: GS
authors.lastname: Pettis
mesh_terms: D002118:Calcium / Q000378:metabolism; D002412:Cations / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D008345:Manganese / Q000378:metabolism*; D010641:Phenotype; D011135:Polysaccharides, Bacterial / Q000378:metabolism; D014481:United States; D041261:Vibrio vulnificus / Q000187:drug effects* / Q000254:growth & development* / Q000378:metabolism
chemical_list: D002412:Cations; D003470:Culture Media; D011135:Polysaccharides, Bacterial; D008345:Manganese; D002118:Calcium