TABLE 3

Regulation of genes required for virulence in humans by either (p)ppGpp or DksA

Gene(s)aFunction35000HPΔrelAΔspoT/35000HPb,c35000HPΔdksA/35000HPb,d
Fully attenuated
    flp-1flp-2flp-3Adherence and microcolony formation−3.72−2.33e
    tadAAdherence and microcolony formation−6.86
    dsrAMajor role in serum resistance
    lspA1, lspA2Escape from phagocytosis−2.75, −5.36f−2.57f
    ncaACollagen binding
    hgbAHeme and/or iron uptake−2.54−2.37
    palOuter membrane stability
    hfqRNA binding chaperone11.672.64
    sapB-sapCResistance to antimicrobial peptides
    cpxATwo-component sensor kinase
Partially attenuated
    dltAPartial role in serum resistance4.98
    wecAInitiates synthesis of putative glycoconjugate
    luxSQuorum sensing
    fgbAFibrinogen binding2.04
    sapAResistance to antimicrobial peptides
    csrAPosttranscriptional regulation−2.34
    dksADnaK repressor; (p)ppGpp cofactorNA
    relA, spoT(p)ppGpp synthetase and hydrolase; stringent responseNA2.09 (spoT)
  • a Strains with mutated genes that have been tested in human volunteers and classified as fully or partially attenuated.

  • b Fold change of the first differentially regulated gene in the operon. –, no change in expression; NA, not applicable.

  • c Fold change in 35000HPΔrelAΔspoT mutant relative to 35000HP strain in stationary phase.

  • d Fold change in 35000HPΔdksA mutant relative to 35000HP strain in stationary phase.

  • e Fold change of flp-3 only.

  • f Fold change of the lspB-lspA2 operon.