title: Characteristics of human intestinal Escherichia coli with changing environments.
abstract: To investigate if the characteristics of human intestinal Escherichia coli are changing with the environment of the host, we studied intestinal E. coli from subjects having recently migrated from a temperate to a tropical area. We determined the phylogenetic group, the prevalence of the antibiotic resistance, the presence of integrons and the strain diversity in faecal isolates from 25 subjects originally from metropolitan France and expatriated to French Guyana. These characteristics were compared with those of 25 previously studied Wayampi Amerindian natives of French Guyana and from 25 metropolitan French residents. The three groups of subjects were matched for age and sex, had not taken antibiotics for at least 1 month, nor had been hospitalized within the past year. In all, the characteristics of intestinal E. coli from Expatriates were intermediate between those found in residents from metropolitan France and those found in natives of French Guyana. Prevalence of carriage of resistant Gram-negative bacteria in Expatriates was intermediate between French residents and Wayampi as were the prevalence of integrons in E. coli (12.3% versus 16.3% and 7.8% respectively), and the intra-host diversity of E. coli (2.3 strains/subject versus 1.9 and 3.1, respectively); lastly, in Expatriates, the prevalence of carriage of phylogenetic group B2 strains was lower than in French residents (16% versus 56%, P = 0.005), while carriage of phylogenetic group A strains was lower than in Wayampi (56% versus 88%, P = 0.03). Our results suggest that the composition of the commensal intestinal flora of humans is not static but changes dynamically in response to new environmental conditions.
authors.affiliation: EA3964 <<Résistance bactérienne in vivo>> Faculté de Médecine, Université Paris 7 and Hôpital Bichat APHP, 75018 Paris, France.
authors.forename: David
authors.initials: D
authors.lastname: Skurnik
authors.forename: Daniel
authors.initials: D
authors.lastname: Bonnet
authors.forename: Claire
authors.initials: C
authors.lastname: Bernède-Bauduin
authors.forename: Rémy
authors.initials: R
authors.lastname: Michel
authors.forename: Christian
authors.initials: C
authors.lastname: Guette
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Becker
authors.forename: Corinne
authors.initials: C
authors.lastname: Balaire
authors.forename: Françoise
authors.initials: F
authors.lastname: Chau
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Mohler
authors.forename: Vincent
authors.initials: V
authors.lastname: Jarlier
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Boutin
authors.forename: Brigitte
authors.initials: B
authors.lastname: Moreau
authors.forename: Didier
authors.initials: D
authors.lastname: Guillemot
authors.forename: Erick
authors.initials: E
authors.lastname: Denamur
authors.forename: Antoine
authors.initials: A
authors.lastname: Andremont
authors.forename: Raymond
authors.initials: R
authors.lastname: Ruimy
mesh_terms: D002353:Carrier State / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004641:Emigration and Immigration; D004926:Escherichia coli / Q000145:classification* / Q000187:drug effects / Q000235:genetics*; D005260:Female; D005602:France; D005616:French Guiana; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D007199:Indians, South American / Q000208:ethnology; D008297:Male; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D014195:Travel