A metabolic operon in extraintestinal pathogenic Escherichia coli promotes fitness under stressful conditions and invasion of eukaryotic cells.
We identified a carbohydrate metabolic operon (frz) that is highly associated with extraintestinal pathogenic Escherichia coli (ExPEC) strains. The frz operon codes for three subunits of a phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) transporter of the fructose subfamily, for a transcriptional activator of PTSs of the MgA family, for two type II ketose-1,6-bisphosphate aldolases, for a sugar-specific kinase (repressor, open reading frame, kinase family [ROK]), and for a protein of the cupin superfamily. We proved that the frz operon promotes bacterial fitness under stressful conditions, such as oxygen restriction, late stationary phase of growth, or growth in serum or in the intestinal tract. Furthermore, we showed that frz is involved in adherence to and internalization in human type II pneumocytes, human enterocytes, and chicken liver cells by favoring the ON orientation of the fim operon promoter and thus acting on the expression of type 1 fimbriae, which are the major ExPEC adhesins. Both the PTS activator and the metabolic enzymes encoded by the frz operon are involved in these phenotypes.
Rouquet
Géraldine
G
INRA, UR1282, Unité d'Infectiologie Animale et de Santé Publique, Laboratoire de Pathogénie Bactérienne, Centre de Recherche de Tours, Nouzilly, France.
Porcheron
Gaëlle
G
Barra
Claire
C
Répérant
Maryline
M
Chanteloup
Nathalie K
NK
Schouler
Catherine
C
Gilot
Philippe
P
D000818:Animals; D002460:Cell Line; D002645:Chickens; D006224:Cricetinae; D004926:Escherichia coli / Q000235:genetics* / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics / Q000502:physiology; D006801:Humans; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D009876:Operon / Q000235:genetics / Q000502:physiology*; D018384:Oxidative Stress / Q000235:genetics; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014774:Virulence / Q000235:genetics*
D010731:Phosphoenolpyruvate Sugar Phosphotransferase System