title: Spermidine regulates Vibrio cholerae biofilm formation via transport and signaling pathways.
abstract: Vibrio cholerae, the causative agent of the devastating diarrheal disease cholera, can form biofilms on diverse biotic and abiotic surfaces. Biofilm formation is important for the survival of this organism both in its natural environment and in the human host. Development of V. cholerae biofilms are regulated by complex regulatory networks that respond to environmental signals. One of these signals, norspermidine, is a polyamine that enhances biofilm formation via the NspS/MbaA signaling system. In this work, we have investigated the role of the polyamine spermidine in regulating biofilm formation in V. cholerae. We show that spermidine import requires PotD1, an ortholog of the periplasmic substrate-binding protein of the spermidine transport system in Escherichia coli. We also show that deletion of the potD1 gene results in a significant increase in biofilm formation. We hypothesize that spermidine imported into the cell hinders biofilm formation. Exogenous spermidine further reduces biofilm formation in a PotD1-independent, but NspS/MbaA-dependent, manner. Our results suggest that polyamines affect biofilm formation in V. cholerae via multiple pathways involving both transport and signaling networks.
authors.affiliation: Department of Biology, Appalachian State University, 572 Rivers Street, Boone, NC 28607, USA.
authors.forename: Marcus W
authors.initials: MW
authors.lastname: McGinnis
authors.forename: Zachary M
authors.initials: ZM
authors.lastname: Parker
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Walter
authors.forename: Alex C
authors.initials: AC
authors.lastname: Rutkovsky
authors.forename: Claudia
authors.initials: C
authors.lastname: Cartaya-Marin
authors.forename: Ece
authors.initials: E
authors.lastname: Karatan
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development*; D001692:Biological Transport; D017353:Gene Deletion; D006801:Humans; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013095:Spermidine / Q000378:metabolism*; D014734:Vibrio cholerae / Q000187:drug effects* / Q000254:growth & development*
chemical_list: D001426:Bacterial Proteins; D026901:Membrane Transport Proteins; D013095:Spermidine