title: Population structure and uropathogenic virulence-associated genes of faecal Escherichia coli from healthy young and elderly adults.
abstract: We investigated the population structures of faecal Escherichia coli in 30 healthy young adults (13 males and 17 females) aged between 20 and 45 years and 29 elderly adults (14 females and 15 males) aged between 65 and 77 years. In all, 1566 strains were typed with the PhPlate system and grouped into biochemical phenotypes (BPTs). Strains with shared BPTs were further typed using randomly amplified polymorphic DNA analysis. Forty-four per cent of the strains were shared between two or more age and gender groups. Elders had a significantly higher (P<0.001) number of BPTs (mean±standard error 3.3±0.27) than younger groups (1.82±0.27). Phylogenetic affiliation and virulence-associated genes (VAGs) of the strains showed that more than 80 % of the strains belonging to dominant types belonged to phylogroups B2 and D. Amongst dominant BPTs, phylogenetic group A was significantly associated with females (P<0.0001), and elders were more likely to carry group D (P<0.0124). Elderly males had a higher prevalence of VAGs than young males (P<0.0001) and young females (P<0.0005). We conclude that there is a lower prevalence of E. coli with uropathogenic properties in healthy young adults than in elders.
authors.affiliation: Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia.
authors.forename: Tara L
authors.initials: TL
authors.lastname: Vollmerhausen
authors.affiliation: Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia.
authors.forename: Nubia L
authors.initials: NL
authors.lastname: Ramos
authors.affiliation: Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia.
authors.forename: Aycan
authors.initials: A
authors.lastname: Gündoğdu
authors.affiliation: School of Environmental Sciences, Charles Sturt University, Thurgoona, NSW 2641, Australia.
authors.forename: Wayne
authors.initials: W
authors.lastname: Robinson
authors.affiliation: Department of Clinical Microbiology, MTC, Karolinska University Hospital, S-171 76 Stockholm, Sweden.
authors.forename: Annelie
authors.initials: A
authors.lastname: Brauner
authors.affiliation: Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Katouli
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001483:Base Sequence; D016172:DNA Fingerprinting; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D005260:Female; D005798:Genes, Bacterial; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D010802:Phylogeny; D012737:Sex Factors; D014552:Urinary Tract Infections / Q000382:microbiology*; D014774:Virulence / Q000235:genetics; D055815:Young Adult
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial