Impact of Salt and Nutrient Content on Biofilm Formation by Vibrio fischeri Journal Article

Authors: Marsden, A. E.; Grudzinski, K.; Ondrey, J. M.; DeLoney-Marino, C. R.; Visick, K. L.
Article Title: Impact of Salt and Nutrient Content on Biofilm Formation by Vibrio fischeri
Abstract: Vibrio fischeri, a marine bacterium and symbiont of the Hawaiian bobtail squid Euprymna scolopes, depends on biofilm formation for successful colonization of the squid#39;s symbiotic light organ. Here, we investigated if culture conditions, such as nutrient and salt availability, affect biofilm formation by V. fischeri by testing the formation of wrinkled colonies on solid media. We found that V. fischeri forms colonies with more substantial wrinkling when grown on the nutrient-dense LBS medium containing NaCl relative to those formed on the more nutrient-poor, seawater-salt containing SWT medium. The presence of both tryptone and yeast extract was necessary for the production of quot;normalquot; wrinkled colonies; when grown on tryptone alone, the colonies displayed a divoting phenotype and were attached to the agar surface. We also found that the type and concentration of specific seawater salts influenced the timing of biofilm formation. Of the conditions assayed, wrinkled colony formation occurred earliest in LBS(-Tris) media containing 425 mM NaCl, 35 mM MgSO4, and 5 mM CaCl2. Pellicle formation, another measure of biofilm development, was also enhanced in these growth conditions. Therefore, both nutrient and salt availability contribute to V. fischeri biofilm formation. While growth was unaffected, these optimized conditions resulted in increased syp locus expression as measured by a PsypA-lacZ transcriptional reporter. We anticipate these studies will help us understand how the natural environment of V. fischeri affects its ability to form biofilms and, ultimately, colonize E. scolopes.
Journal Title: PloS one
Volume: 12
Issue: 1
ISSN: 1932-6203; 1932-6203
Publisher: Unknown  
Journal Place: United States
Date Published: 2017
Start Page: e0169521
Language: eng
Notes: LR: 20170224; GR: R01 GM059690/GM/NIGMS NIH HHS/United States; GR: R01 GM114288/GM/NIGMS NIH HHS/United States; JID: 101285081; 2016/08/25 [received]; 2016/12/19 [accepted]; epublish