TABLE 2.

Transcriptome analysis for definition of the Fnr regulona

GeneDescriptionPutative Fnr boxInduction/repression (fold)
FermentationNitrate respiration
Group 1
    narGNitrate reductase (alpha subunit)++1.31.0
    narHNitrate reductase (beta subunit)2.01.8
    narIAssembling factor2.15.6
    narJNitrate reductase (gamma subunit)3.11.9
    narKNitrite extrusion protein++1.61.4
    fnrAnaerobic redox regulator1.64.1
    arfMAnaerobic modulator++1.72.2
Group 2
    alsSAlpha-acetolactate decarboxylase+(1.3)(1.9)
    alsDAlpha-acetolactate synthase(2.8)(2.2)
    cydACytochrome bd ubiquinol oxidase (I)(1.8)(1.3)
    cydBCytochrome bd ubiquinol oxidase (II)(1.4)(3.3)
    cydCABC transporter(1.3)(2.5)
    cydDABC transporter(1.4)(2.0)
    ldhl-Lactate dehydrogenase+(1.4)(17.6)
    lctPl-Lactate permease(0.9)(4.0)
    ywcJSimilar to formate/nitrite transporter+(1.2)(1.4)
Group 3
    dhbA2,3-Dihydro-2,3-DHB dehydrogenase1.61.8
    dhbBIsochorismatase1.35.5
    dhbCIsochorismate synthase1.55.1
    dhbE2,3-DHB-AMP ligase1.12.7
    dhbFSimilar to E. coli EntF1.14.5
    hmpFlavohemoglobin1.233.3
    nasDNitrite reductase; subunit1.012.4
    nasENitrite reductase; subunit1.14.6
    nasFUropophyrin-III C-methyltransferase0.96.9
    ycgTSimilar to thioredoxin reductase1.22.5
    ydbNUnknown1.311.4
    ykjAUnknown0.93.5
    ykuNUnknown; similar to flavodoxin1.55.5
    ykuOUnknown1.919.5
    ykuPUnknown; similar to flavodoxin1.329.8
Group 4
    acoAAcetoin dehydrogenase; E1 subunit7.18.6
    acoBAcetoin dehydrogenase; E1 subunit2.52.8
    acoCAcetoin dehydrogenase; E2 component5.33.4
    acoLAcetoin dehydrogenase; E3 component4.14.5
  • a Total cellular RNA was prepared from wild-type B. subtilis and a corresponding fnr mutant strain grown anaerobically under the indicated conditions. Numbers give the severalfold induction and, when shown in parentheses, the severalfold repression mediated by Fnr. ++, Fnr boxes in the promoter region of the indicated genes responsible for a direct Fnr effect; +, found Fnr boxes without direct function; −, no Fnr box found.