title: A Vibrio cholerae protease needed for killing of Caenorhabditis elegans has a role in protection from natural predator grazing.
abstract: Vibrio cholerae is the causal bacterium of the diarrheal disease cholera, and its growth and survival are thought to be curtailed by bacteriovorous predators, e.g., ciliates and flagellates. We explored Caenorhabditis elegans as a test organism after finding that V. cholerae can cause lethal infection of this nematode. By reverse genetics we identified an extracellular protease, the previously uncharacterized PrtV protein, as being necessary for killing. The killing effect is associated with the colonization of bacteria within the Caenorhabditis elegans intestine. We also show that PrtV is essential for V. cholerae in the bacterial survival from grazing by the flagellate Cafeteria roenbergensis and the ciliate Tetrahymena pyriformis. The PrtV protein appears to have an indirect role in the interaction of V. cholerae with mammalian host cells as judged from tests with tight monolayers of human intestinal epithelial cells. Our results demonstrate a key role for PrtV in V. cholerae interaction with grazing predators, and we establish Caenorhabditis elegans as a convenient organism for identification of V. cholerae factors involved in host interactions and environmental persistence.
authors.affiliation: Molecular Biology and Ecology and Environmental Science, and Umeå Center for Molecular Pathogenesis, Umeå University, SE-90187 Umeå, Sweden.
authors.forename: Karolis
authors.initials: K
authors.lastname: Vaitkevicius
authors.forename: Barbro
authors.initials: B
authors.lastname: Lindmark
authors.forename: Gangwei
authors.initials: G
authors.lastname: Ou
authors.forename: Tianyan
authors.initials: T
authors.lastname: Song
authors.forename: Claudia
authors.initials: C
authors.lastname: Toma
authors.forename: Masaaki
authors.initials: M
authors.lastname: Iwanaga
authors.forename: Jun
authors.initials: J
authors.lastname: Zhu
authors.forename: Agneta
authors.initials: A
authors.lastname: Andersson
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: Hammarström
authors.forename: Simon
authors.initials: S
authors.lastname: Tuck
authors.forename: Sun Nyunt
authors.initials: SN
authors.lastname: Wai
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms; D017173:Caenorhabditis elegans / Q000166:cytology / Q000382:microbiology* / Q000502:physiology*; D002450:Cell Communication; D045744:Cell Line, Tumor; D002772:Cholera Toxin / Q000378:metabolism; D005247:Feeding Behavior; D010861:Fimbriae, Bacterial / Q000378:metabolism; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism; D007422:Intestines / Q000166:cytology / Q000382:microbiology; D010447:Peptide Hydrolases / Q000235:genetics / Q000378:metabolism*; D011235:Predatory Behavior; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D015996:Survival Rate; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014734:Vibrio cholerae / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity*
chemical_list: D001426:Bacterial Proteins; D016209:Interleukin-8; C088907:LuxO protein, Vibrio harveyi; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C064778:LuxR autoinducer binding proteins; D002772:Cholera Toxin; D010447:Peptide Hydrolases; C513132:PrtV protein, Vibrio cholerae