Infections with extraintestinal avian pathogenic Escherichia coli (APEC) cause significant economic losses in the poultry industry worldwide. In a previous study we applied signature-tagged transposon mutagenesis and identified 28 virulence-associated genes in APEC strain IMT5155 (O2 : H5 : K1). One of them, yjjQ, encodes a putative transcriptional regulator whose function and role in pathogenesis are still unknown. In the present study, this mutant has been characterized. The yjjQ-defective mutant of IMT5155 (M18E10) was out-competed by the wild-type strain in vivo, and infection of chickens with this yjjQ mutant led to strongly reduced bacterial loads in several organs. Expression studies showed that transcription of yjjQ was significantly upregulated in M9 minimal medium. Correspondingly, the yjjQ mutant showed significantly reduced growth in M9 medium. Although the mutation could not be complemented, a yjjQ deletion mutant showed phenotypes similar to the transposon-generated mutant M18E10, whereas deletion and overexpression of the downstream gene bglJ did not cause a growth defect in M9. To identify virulence genes regulated by YjjQ, one- and two-dimensional protein gel electrophoresis was performed. The proteomic analysis revealed that in the yjjQ mutant M18E10 the expression of several genes involved in iron uptake was downregulated and some other genes were upregulated. The regulation of genes involved in iron uptake was shown to occur at the transcription level using real-time RT-PCR. Taking the results together, this functional analysis strongly suggests that YjjQ is a regulator involved in virulence of APEC by affecting iron uptake.
AusubelF. M.1994Current Protocols In Molecular Biology New York: Wiley;
BlattnerF. R.,
PlunkettG.III,
BlochC. A.,
PernaN. T.,
BurlandV.,
RileyM.,
Collado-VidesJ.,
GlasnerJ. D.,
RodeC. K. & other authors; 1997; The complete genome sequence of Escherichia coli K-12. Science 277:1453–1474
ChirwaN. T.,
HerringtonM. B.2003; CsgD, a regulator of curli and cellulose synthesis, also regulates serine hydroxymethyltransferase synthesis in Escherichia coli K-12. Microbiology 149:525–535
DatsenkoK. A.,
WannerB. L.2000; One-step inactivation of chromosomal genes in Escherichia coli K-12 using PCR products. Proc Natl Acad Sci U S A 97:6640–6645
EwersC.,
LiG.,
WilkingH.,
AltK.,
AntáoE. M.,
LaturnusC.,
DiehlI.,
GloddeS.,
HomeierT.other authors2007; Avian pathogenic, uropathogenic, and newborn meningitis-causing Escherichia coli: how closely related are they?. Int J Med Microbiol 297:163–176
FuchsT. M.,
SchneiderB.,
KrumbachK.,
EggelingL.,
GrossR.2000; Characterization of a Bordetella pertussis diaminopimelate (DAP) biosynthesis locus identifies dapC, a novel gene coding for an N-succinyl-l,l-DAP aminotransferase. J Bacteriol 182:3626–3631
HantkeK.,
BraunV.1998; Control of bacterial iron transport by regulatory proteins. In Metal Ions in Gene Regulation pp 11–44 Edited by
SilverS.,
Walden.
New York: Chapman & Hall;
HayashiT.,
MakinoK.,
OhnishiM.,
KurokawaK.,
IshiiK.,
YokoyamaK.,
HanC. G.,
OhtsuboE.,
NakayamaK.& other authors2001; Complete genome sequence of enterohemorrhagic Escherichia coli O157 : H7 and genomic comparison with a laboratory strain K-12. DNA Res 8:11–22
IngrahamJ. L.,
Brooks LowK.,
MagasanikB.,
SchaechterM.,
UmbargerH. E.1987Escherichia coli and Salmonella Typhimurium: Cellular and Molecular Biology Washington, DC: American Society for Microbiology;
JanakiramanA.,
SlauchJ. M.2000; The putative iron transport system SitABCD encoded on SPI1 is required for full virulence of Salmonella typhimurium. Mol Microbiol 35:1146–1155
JohnsonJ. R.,
ClabotsC.,
RosenH.2006a; Effect of inactivation of the global oxidative stress regulator oxyR on the colonization ability of Escherichia coli O1 : K1 : H7 in a mouse model of ascending urinary tract infection. Infect Immun 74:461–468
JohnsonT. J.,
JohnsonS. J.,
NolanL. K.2006b; Complete DNA sequence of a ColBM plasmid from avian pathogenic Escherichia coli suggests that it evolved from closely related ColV virulence plasmids. J Bacteriol 188:5975–5983
JohnsonT. J.,
SiekK. E.,
JohnsonS. J.,
NolanL. K.2006c; DNA sequence of a ColV plasmid and prevalence of selected plasmid-encoded virulence genes among avian Escherichia coli strains. J Bacteriol 188:745–758
KariyawasamS.,
JohnsonT. J.,
DebroyC.,
NolanL. K.2006a; Occurrence of pathogenicity island I (APEC-O1) genes among Escherichia coli implicated in avian colibacillosis. Avian Dis 50:405–410
KariyawasamS.,
JohnsonT. J.,
NolanL. K.2006b; The pap operon of avian pathogenic Escherichia coli strain O1 : K1 is located on a novel pathogenicity island. Infect Immun 74:744–749
LucasR. L.,
LeeC. A.2001; Roles of hilC and hilD in regulation of hilA expression in Salmonella enterica serovar Typhimurium. J Bacteriol 183:2733–2745
MadhusudanS.,
PauknerA.,
KlingenY.,
SchnetzK.2005; Independent regulation of H-NS-mediated silencing of the bgl operon at two levels: upstream by BglJ and LeuO and downstream by DnaKJ. Microbiology 151:3349–3359
MelliesJ. L.,
BarronA. M.,
HaackK. R.,
KorsonA. S.,
OldridgeD. A.2006; The global regulator Ler is necessary for enteropathogenic Escherichia coli colonization of Caenorhabditis elegans. Infect Immun 74:64–72
MillerJ. H.1972Experiments in Molecular Genetics Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
MillsM.,
PayneS. M.1995; Genetics and regulation of heme iron transport in Shigella dysenteriae and detection of an analogous system in Escherichia coli O157 : H7. J Bacteriol 177:3004–3009
PauknerA.2007Ein Regulationsnetzwerk aus H-NS und den Antireperessoren BglJ und LeuO PhD thesis Institute for Genetics, University of Cologne; Germany:
PuopoloK. M.,
HollingsheadS. K.,
CareyV. J.,
MadoffL. C.2001; Tandem repeat deletion in the alpha C protein of group B streptococcus is recA independent. Infect Immun 69:5037–5045
RieulC.,
BleicherF.,
DuclosB.,
CortayJ. C.,
CozzoneA. J.1988; Nucleotide sequence of the aceA gene coding for isocitrate lyase in Escherichia coli. Nucleic Acids Res 16:5689
Rodriguez-SiekK. E.,
GiddingsC. W.,
DoetkottC.,
JohnsonT. J.,
FakhrM. K.,
NolanL. K.2005a; Comparison of Escherichia coli isolates implicated in human urinary tract infection and avian colibacillosis. Microbiology 151:2097–2110
Runyen-JaneckyL. J.,
ReevesS. A.,
GonzalesE. G.,
PayneS. M.2003; Contribution of the Shigella flexneri Sit, Iuc, and Feo iron acquisition systems to iron acquisition in vitro and in cultured cells. Infect Immun 71:1919–1928
RussoT. A.,
JohnsonJ. R.2000; Proposal for a new inclusive designation for extraintestinal pathogenic isolates of Escherichia coli: ExPEC. J Infect Dis 181:1753–1754
RussoT. A.,
CarlinoU. B.,
JohnsonJ. R.2001; Identification of a new iron-regulated virulence gene, ireA, in an extraintestinal pathogenic isolate of Escherichia coli. Infect Immun 69:6209–6216
SabriM.,
LeveilleS.,
DozoisC. M.2006; A SitABCD homologue from an avian pathogenic Escherichia coli strain mediates transport of iron and manganese and resistance to hydrogen peroxide. Microbiology 152:745–758
SchmittgenT. D.,
ZakrajsekB. A.,
MillsA. G.,
GornV.,
SingerM. J.,
ReedM. W.2000; Quantitative reverse transcription-polymerase chain reaction to study mRNA decay: comparison of endpoint and real-time methods. Anal Biochem 285:194–204
SchmitzG.,
DownsD. M.2004; Reduced transaminase B (IlvE) activity caused by the lack of yjgF is dependent on the status of threonine deaminase (IlvA) in Salmonella enterica serovar Typhimurium. J Bacteriol 186:803–810
SeputieneV.,
MotiejunasD.,
SuziedelisK.,
TomeniusH.,
NormarkS.,
MeleforsO.,
SuziedelieneE.2003; Molecular characterization of the acid-inducible asr gene of Escherichia coli and its role in acid stress response. J Bacteriol 185:2475–2484
StancikL. M.,
StancikD. M.,
SchmidtB.,
BarnhartD. M.,
YonchevaY. N.,
SlonczewskiJ. L.2002; pH-dependent expression of periplasmic proteins and amino acid catabolism in Escherichia coli. J Bacteriol 184:4246–4258
SturmeM. H.,
NakayamaJ.,
MolenaarD.,
MurakamiY.,
KunugiR.,
FujiiT.,
VaughanE. E.,
KleerebezemM.,
de VosW. M.2005; An agr-like two-component regulatory system in Lactobacillus plantarum is involved in production of a novel cyclic peptide and regulation of adherence. J Bacteriol 187:5224–5235
TremouletF.,
DucheO.,
NamaneA.,
MartinieB.,
LabadieJ. C.2002; A proteomic study of Escherichia coli O157 : H7 NCTC 12900 cultivated in biofilm or in planktonic growth mode. FEMS Microbiol Lett 215:7–14
VaaraM.,
NurminenM.1999; Outer membrane permeability barrier in Escherichia coli mutants that are defective in the late acyltransferases of lipid A biosynthesis. Antimicrob Agents Chemother 43:1459–1462
ValvanoM. A.,
MaroldaC. L.,
BittnerM.,
Glaskin-ClayM.,
SimonT. L.,
KlenaJ. D.2000; The rfaE gene from Escherichia coli encodes a bifunctional protein involved in biosynthesis of the lipopolysaccharide core precursor ADP-l-glycero-d- manno-heptose. J Bacteriol 182:488–497
WelchR. A.,
BurlandV.,
PlunkettG.III,
RedfordP.,
RoeschP.,
RaskoD.,
BucklesE. L.,
LiouS. R.,
BoutinA.other authors2002; Extensive mosaic structure revealed by the complete genome sequence of uropathogenic Escherichia coli. Proc Natl Acad Sci U S A 99:17020–17024
ZhouD.,
HardtW. D.,
GalanJ. E.1999; Salmonella typhimurium encodes a putative iron transport system within the centisome 63 pathogenicity island. Infect Immun 67:1974–1981