title: Secretory IgA and mucin-mediated biofilm formation by environmental strains of Escherichia coli: role of type 1 pili.
abstract: Recent studies suggest the importance of secretory IgA (SIgA) and mucin in the mediation of biofilm formation by commensal bacteria within the mammalian gut. Studies using a variety of strains of Escherichia coli have indicated that the interaction between E. coli and SIgA is dependent on the type 1 pilus. In this study, the importance of the pilus in SIgA-mediated biofilm formation by a laboratory strain (MG1655) and environmental (fecal) strains of E. coli was evaluated. Transient expression of the type 1 pilus by the laboratory strain of E. coli failed to facilitate SIgA-mediated biofilm formation, whereas constitutive expression of the type 1 pilus by the laboratory strain was sufficient. In contrast, transient expression of the type 1 pilus was sufficient to facilitate SIgA-mediated biofilm formation by environmental isolates. The "threshold" for mucin-mediated biofilm formation appeared to be lower than that for SIgA-mediated biofilm formation, perhaps reflecting disparate roles of mucin and SIgA in mediating biofilm formation in the gut. These studies also provide the first procedures for the growth of bacterial biofilms on live epithelial cells in vitro, an important development that may facilitate future studies on the effects of bacterial biofilms on epithelial cells.
authors.affiliation: Department of Surgery, Duke University Medical Center, Box 2605, Durham, NC 27710, USA.
authors.forename: R Randal
authors.initials: RR
authors.lastname: Bollinger
authors.forename: Mary Lou
authors.initials: ML
authors.lastname: Everett
authors.forename: Shaina D
authors.initials: SD
authors.lastname: Wahl
authors.forename: Yu-Huei
authors.initials: YH
authors.lastname: Lee
authors.forename: Paul E
authors.initials: PE
authors.lastname: Orndorff
authors.forename: William
authors.initials: W
authors.lastname: Parker
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology; D000818:Animals; D001422:Bacterial Adhesion / Q000502:physiology*; D018441:Biofilms; D045744:Cell Line, Tumor / Q000382:microbiology; D003110:Colonic Neoplasms / Q000473:pathology; D004926:Escherichia coli / Q000302:isolation & purification; D048168:Escherichia coli K12 / Q000502:physiology*; D005243:Feces / Q000382:microbiology; D005260:Female; D010861:Fimbriae, Bacterial / Q000502:physiology*; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000302:isolation & purification / Q000502:physiology*; D037241:Mannose-Binding Lectins / Q000502:physiology; D008567:Membranes, Artificial; D051379:Mice / Q000382:microbiology; D008895:Milk, Human / Q000276:immunology; D009077:Mucins / Q000502:physiology*; D011137:Polystyrenes; D013045:Species Specificity
chemical_list: D007071:Immunoglobulin A, Secretory; D037241:Mannose-Binding Lectins; D008567:Membranes, Artificial; D009077:Mucins; D011137:Polystyrenes