title: Expression of cellulose and curli fimbriae by Escherichia coli isolated from the gastrointestinal tract.
abstract: Escherichia coli colonizes the gastrointestinal tract of humans; however, little is known about the features of commensal strains. This study investigated whether expression of the biofilm extracellular matrix components cellulose and curli fimbriae is found among commensal isolates. Fifty-two E. coli strains were isolated from faecal samples and, as a control, 24 strains from urinary tract infections were also used. Faecal isolates were characterized by serotyping and phylogenetically grouped by PCR. The genotype was determined by PFGE and the presence of virulence factors was assessed. Co-expression of cellulose and curli fimbriae at 28 degrees C and 37 degrees C was typical for faecal isolates, while urinary tract infection strains typically expressed the extracellular matrix components at 28 degrees C only. Knockout studies in a representative faecal isolate revealed that the response regulator CsgD regulated cellulose and curli fimbriae, as found previously in Salmonella enterica. In contrast to S. enterica, at 37 degrees C pellicle formation occurred in the absence of cellulose and curli fimbriae. The gastrointestinal tract represents a source of biofilm-forming bacteria, which can spread to susceptible sites.
authors.affiliation: Department of Cell Biology and Immunology, Gesellschaft für Biotechnologische Forschung, 38124 Braunschweig, Germany 2Microbiology and Tumor Biology Center (MTC), Karolinska Institutet, 171 77 Stockholm, Sweden 3National Reference Centre for Salmonella and other Enterics, Robert Koch Institute, Bereich Wernigerode, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Bokranz
authors.affiliation: Department of Cell Biology and Immunology, Gesellschaft für Biotechnologische Forschung, 38124 Braunschweig, Germany 2Microbiology and Tumor Biology Center (MTC), Karolinska Institutet, 171 77 Stockholm, Sweden 3National Reference Centre for Salmonella and other Enterics, Robert Koch Institute, Bereich Wernigerode, Germany.
authors.forename: Xiaoda
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Cell Biology and Immunology, Gesellschaft für Biotechnologische Forschung, 38124 Braunschweig, Germany 2Microbiology and Tumor Biology Center (MTC), Karolinska Institutet, 171 77 Stockholm, Sweden 3National Reference Centre for Salmonella and other Enterics, Robert Koch Institute, Bereich Wernigerode, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Tschäpe
authors.affiliation: Department of Cell Biology and Immunology, Gesellschaft für Biotechnologische Forschung, 38124 Braunschweig, Germany 2Microbiology and Tumor Biology Center (MTC), Karolinska Institutet, 171 77 Stockholm, Sweden 3National Reference Centre for Salmonella and other Enterics, Robert Koch Institute, Bereich Wernigerode, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Römling
mesh_terms: D000293:Adolescent; D000328:Adult; D002482:Cellulose / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure*; D004927:Escherichia coli Infections / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D010861:Fimbriae, Bacterial / Q000648:ultrastructure*; D041981:Gastrointestinal Tract / Q000382:microbiology*; D005838:Genotype; D006801:Humans; D007223:Infant; D008875:Middle Aged; D010802:Phylogeny; D014552:Urinary Tract Infections / Q000382:microbiology
chemical_list: D002482:Cellulose