title: Environmental and genetic factors that contribute to Escherichia coli K-12 biofilm formation.
abstract: Biofilms are communities of bacteria whose formation on surfaces requires a large portion of the bacteria's transcriptional network. To identify environmental conditions and transcriptional regulators that contribute to sensing these conditions, we used a high-throughput approach to monitor biofilm biomass produced by an isogenic set of Escherichia coli K-12 strains grown under combinations of environmental conditions. Of the environmental combinations, growth in tryptic soy broth at 37 degrees C supported the most biofilm production. To analyze the complex relationships between the diverse cell-surface organelles, transcriptional regulators, and metabolic enzymes represented by the tested mutant set, we used a novel vector-item pattern-mining algorithm. The algorithm related biofilm amounts to the functional annotations of each mutated protein. The pattern with the best statistical significance was the gene ontology 'pyruvate catabolic process,' which is associated with enzymes of acetate metabolism. Phenotype microarray experiments illustrated that carbon sources that are metabolized to acetyl-coenzyme A, acetyl phosphate, and acetate are particularly supportive of biofilm formation. Scanning electron microscopy revealed structural differences between mutants that lack acetate metabolism enzymes and their parent and confirmed the quantitative differences. We conclude that acetate metabolism functions as a metabolic sensor, transmitting changes in environmental conditions to biofilm biomass and structure.
authors.affiliation: Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108-6050, USA. Birgit.Pruess@ndsu.edu
authors.forename: Birgit M
authors.initials: BM
authors.lastname: Prüss
authors.forename: Karan
authors.initials: K
authors.lastname: Verma
authors.forename: Priyankar
authors.initials: P
authors.lastname: Samanta
authors.forename: Preeti
authors.initials: P
authors.lastname: Sule
authors.forename: Sunil
authors.initials: S
authors.lastname: Kumar
authors.forename: Jianfei
authors.initials: J
authors.lastname: Wu
authors.forename: David
authors.initials: D
authors.lastname: Christianson
authors.forename: Shelley M
authors.initials: SM
authors.lastname: Horne
authors.forename: Shane J
authors.initials: SJ
authors.lastname: Stafslien
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Wolfe
authors.forename: Anne
authors.initials: A
authors.lastname: Denton
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D000465:Algorithms; D018441:Biofilms / Q000254:growth & development*; D003470:Culture Media; D004777:Environment; D048168:Escherichia coli K12 / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development*; D015964:Gene Expression Regulation, Bacterial; D008855:Microscopy, Electron, Scanning; D020411:Oligonucleotide Array Sequence Analysis; D010363:Pattern Recognition, Automated; D013696:Temperature
chemical_list: D003470:Culture Media; D019342:Acetic Acid