EC Number   |
General Information |
Reference |
|---|
   1.7.5.1 | malfunction |
quinone site variants Lys86 and Gly65, Q-site inhibitor HOQNO, and their effects on heme bD, overview |
741900 |
| 1.7.5.1 | metabolism |
demethylmenasemiquinone and menasemiquinone bind in a similar and strongly asymmetric manner through a short H-bond, caused by slightly inequivalent contributions from two beta-methylene protons of the isoprenoid side chain. Their large isotropic hyperfine coupling constants are consistent with both a specific highly asymmetric binding mode of (demethyl)menasemiquinone and a near in-plane orientation of its isoprenyl chain at Cbeta relative to the aromatic ring, which differs by about 90° to that predicted for free or NarGHI-bound menaquinol |
764215 |
| 1.7.5.1 | metabolism |
in resting spores the Nar1 nitrate reductase requires a functional cytochrome bcc-aa3 supercomplex to reduce nitrate. Mutants lacking the complete qcr-cta genetic locus show no Nar1-dependent nitrate reduction |
-, 765007 |
| 1.7.5.1 | metabolism |
NarJ serves as a chaperone for both the anaerobic respiratory nitrate reductase (NarG) and the assimilatory nitrate reductase NasC (cf. EC 1.7.1.1), the latter of which is active during both aerobic and anaerobic nitrate assimilation. Both NasC and NarG are inactive in the absence of NarJ. 50% of NarJ binds in a 1:1 complex with NasC and the remaining 50% binds in a 1:1 complex with NarG |
-, 765398 |
| 1.7.5.1 | metabolism |
nitrate enters the periplasm through porins where it is reduced to nitrite by the periplasmic nitrate reductase (Nap) or it is further transported into the bacterial cytosol by NarK and serves as an electron acceptor for nitrate reductase A (NarG). Periplasmic nitrite is further converted to NH3 by the periplasmic nitrite reductase (Nrf). Electrons required for these reactions can be transferred to the quinone (Q) pool by NADH:ubiquinone oxidoreductase (Nuo) in a reaction coupled to energy-conserving proton translocation |
-, 742333 |
| 1.7.5.1 | more |
NarGHI comprises a catalytic subunit (NarG, 140 kDa), an electron-transfer subunit (NarH, 58 kDa), and a membrane anchor subunit (NarI, 26 kDa). NarG contains a Mo-bisPGD cofactor that is the site of nitrate reduction as well as a single tetranuclear iron-sulfur ([4Fe-4S]) cluster known as FS0. NarH contains three [4Fe-4S] clusters (FS1-FS3) and one trinuclear iron-sulfur cluster ([3Fe-4S], FS4). NarI anchors the NarGH subunits to the inside of the cytoplasmic membrane and contains two hemes b that are proximal (bP) and distal (bD) to the NarGH subunits, respectively |
741900 |
| 1.7.5.1 | more |
structure-function relationships of quinone reactivity. The NarGHI catalytic activity measured with the demethylmenaquinol (DMKH2) analogue 1,4-naphthoquinol is comparable to that measured using the corresponding methylated methylmenaquinol (MKH2) analogue menadiol, kinetics, overview |
741971 |
| 1.7.5.1 | physiological function |
mutants deficient in all three nitrate reductases narGHI, narXYZ, napFDAGHCB are capable of sustaining 48% of protoporphyrinogen IX oxidases activity and 65% of wild-type activity, respectively |
726366 |
| 1.7.5.1 | physiological function |
NarB, NarGHJI, dehydrogenase MSMEG_2237 and MSMEG_6816 are not required for nitrate reduction as MSMEG_4206 serves as the sole assimilatory nitrate reductase |
-, 765661 |
| 1.7.5.1 | physiological function |
Streptomyces coelicolor has a high capacity for nitrate reduction both during aerobic growth and when the bacterium is incubated anaerobically. During aerobic growth in liquid medium the bacterium is able to reduce 50 mM nitrate stoichiometrically to nitrite. A mutant lacking all three NarGHJI operons fails to reduce nitrate |
-, 725900 |
