title: Curli fimbria: an Escherichia coli adhesin associated with human cystitis.
abstract: Escherichia coli is the major causative agent of human cystitis. In this study, a preliminary molecular analysis carried out by PCR (polymerase chain reaction) demonstrated that 100% of 31 E. coli strains isolated from patients with recurrent UTIs (urinary tract infections) showed the presence of the curli fimbria gene (csgA). Curli fimbria is known to be associated with bacterial biofilm formation but not with the adhesion of human cystitis-associated E. coli. Therefore, this work aimed to study how curli fimbria is associated with uropathogenic E. coli (UPEC) as an adhesion factor. For this purpose, the csgA gene was deleted from strain UPEC-4, which carries three adhesion factor genes (csgA, fimH and ompA). The wild-type UPEC-4 strain and its mutant (ΔcsgA) were analyzed for their adhesion ability over HTB-9 (human bladder carcinoma), Vero (kidney cells of African green monkey) and HUVEC (human umbilical vein) cells in the presence of α-d-mannose. All the wild-type UPEC strains tested (100%) were able to adhere to all three cell types, while the UPEC-4 ΔcsgA mutant lost its adherence to HTB-9 but continued to adhere to the HUVEC and Vero cells. The results suggest that curli fimbria has an important role in the adhesion processes associated with human UPEC-induced cystitis.
authors.affiliation: Departamento de Genética, Evolução e Bioagentes, IB, Universidade Estadual de Campinas, SP, Brazil.
authors.forename: Melina Aparecida
authors.initials: MA
authors.lastname: Cordeiro
authors.affiliation: Departamento de Genética, Evolução e Bioagentes, IB, Universidade Estadual de Campinas, SP, Brazil.
authors.forename: Catierine Hirsch
authors.initials: CH
authors.lastname: Werle
authors.affiliation: Departamento de Genética, Evolução e Bioagentes, IB, Universidade Estadual de Campinas, SP, Brazil.
authors.forename: Guilherme Paier
authors.initials: GP
authors.lastname: Milanez
authors.affiliation: Departamento de Genética, Evolução e Bioagentes, IB, Universidade Estadual de Campinas, SP, Brazil. Electronic address: tyano@unicamp.br.
authors.forename: Tomomasa
authors.initials: T
authors.lastname: Yano
mesh_terms: D018830:Adhesins, Escherichia coli / Q000235:genetics / Q000378:metabolism*; D001422:Bacterial Adhesion; D003556:Cystitis / Q000382:microbiology*; D004927:Escherichia coli Infections / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D017384:Sequence Deletion; D056689:Uropathogenic Escherichia coli / Q000235:genetics / Q000378:metabolism*
chemical_list: D018830:Adhesins, Escherichia coli; D029968:Escherichia coli Proteins; C489688:csgA protein, E coli
keywords: Adhesion; Curli fimbria; Escherichia coli; UPEC