title: Differential expression of iutA and ibeA in the early stages of infection by extra-intestinal pathogenic E. coli.
abstract: Extraintestinal pathogenic Escherichia coli strains are responsible for a number of infections in humans and animals. Several ExPEC virulence genes have already been described such as iutA involved in iron acquisition and ibeA required for invasion of eukaryotic cells. In this study we used the chicken model to study the expression of iutA and ibeA by two ExPEC strains during growth of bacteria in LB medium and during the infection. Expression of iutA and ibeA were shown to be higher in stationary phase than in exponential phase in vitro. During infection, iutA expression was increased at least 50-fold in the airsac and in the lung 3, 6 and 24h. p.i. compared to in vitro grown bacteria. Expression of ibeA was increased 2.5-9-fold in the airsac in the early stages of the infection only. This is the first report analyzing quantitatively the expression of ExPEC virulence genes during the course of the infection. The model described could be useful to study the expression of other ExPEC virulence genes.
authors.affiliation: Laboratoire de Pathogénie Bactérienne, UR 1282 Infectiologie Animale et Santé Publique, INRA - Centre de Tours, 37380 Nouzilly, France.
authors.forename: Iman
authors.initials: I
authors.lastname: Chouikha
authors.forename: Annie
authors.initials: A
authors.lastname: Bree
authors.forename: Maryvonne
authors.initials: M
authors.lastname: Moulin-Schouleur
authors.forename: Philippe
authors.initials: P
authors.lastname: Gilot
authors.forename: Pierre
authors.initials: P
authors.lastname: Germon
mesh_terms: D000400:Air Sacs / Q000382:microbiology; D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis / Q000235:genetics*; D002645:Chickens; D004926:Escherichia coli / Q000235:genetics*; D004927:Escherichia coli Infections / Q000382:microbiology; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics*; D020869:Gene Expression Profiling; D008168:Lung / Q000382:microbiology; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics*; D015854:Up-Regulation; D037521:Virulence Factors / Q000096:biosynthesis*
chemical_list: D001425:Bacterial Outer Membrane Proteins; C096350:CusC protein, E coli; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D037521:Virulence Factors; C034506:aerobactin receptor