NITRATE REDUCTASE STRUCTURE, FUNCTION AND REGULATION: Bridging the Gap between Biochemistry and Physiology.

@article{Campbell1999NITRATERS,
  title={NITRATE REDUCTASE STRUCTURE, FUNCTION AND REGULATION: Bridging the Gap between Biochemistry and Physiology.},
  author={Wilbur H. Campbell},
  journal={Annual review of plant physiology and plant molecular biology},
  year={1999},
  volume={50},
  pages={
          277-303
        }
}
  • W. Campbell
  • Published 1 June 1999
  • Chemistry, Biology
  • Annual review of plant physiology and plant molecular biology
Nitrate reductase (NR; EC 1.6.6.1-3) catalyzes NAD(P)H reduction of nitrate to nitrite. NR serves plants, algae, and fungi as a central point for integration of metabolism by governing flux of reduced nitrogen by several regulatory mechanisms. The NR monomer is composed of a ~100-kD polypeptide and one each of FAD, heme-iron, and molybdenum-molybdopterin (Mo-MPT). NR has eight sequence segments: (a) N-terminal "acidic" region; (b) Mo-MPT domain with nitrate-reducing active site; (c) interface… 

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Structure and function of eukaryotic NAD(P)H:nitrate reductase
  • W. Campbell
  • Chemistry, Biology
    Cellular and Molecular Life Sciences CMLS
  • 2001
TLDR
Recombinant expression of holo-NR and its fragments, including site-directed mutagenesis of key acative site and domain interface residues, are expected to make large contributions to this effort to understand the catalytic mechanism of NR.
Kinetic analysis of 14-3-3-inhibited Arabidopsis thaliana nitrate reductase.
TLDR
It is demonstrated that among different calcium-dependent protein kinases (CPKs), CPK-17 efficiently phosphorylates Ser534 in NR, and it is proposed that 14-3-3 binding toSer534 blocks the transfer of electrons from heme to nitrate by arresting the domain movement via hinge 1.
Molecular Mechanism of 14-3-3 Protein-mediated Inhibition of Plant Nitrate Reductase*
TLDR
It is concluded that 14-3-3 most likely inhibits nitrate reductase by inducing a conformational change that significantly increases the distance between the two redox-active sites and is not due to a perturbation of the reduction potentials of either the heme or the molybdenum center.
Post-translational regulation of nitrate reductase: mechanism, physiological relevance and environmental triggers.
TLDR
It is shown that light and oxygen availability are the major external triggers for the rapid and reversible modulation of NR activity, and that sugars and/or sugar phosphates are the internal signals which regulate the protein kinase(s) and phosphatase.
Viscosity Effects on Eukaryotic Nitrate Reductase Activity*
TLDR
It is concluded that both Hinges 1 and 2 appear to be involved in gating IET steps by restricting the movement of the cytochrome b domain relative to the larger nitrate-reducing and electron-donating modules of NaR.
Protein Phosphatase 2A B55 and A Regulatory Subunits Interact with Nitrate Reductase and Are Essential for Nitrate Reductase Activation1[W][OA]
TLDR
It is shown that PP2A is necessary for NR activation by using inducible artificial microRNA to simultaneously knock down the three structural subunits, which revealed overlapping functions in the activation process of NR.
Assimilatory nitrate reductase: lysine 741 participates in pyridine nucleotide binding via charge complementarity.
TLDR
Results indicated that retention of a positively charged side chain at position 741 in the spinach nitrate reductase primary sequence is important for the efficient binding and subsequent oxidation of NADH and that the positively chargedSide chain enhances nucleotide binding via charge complementarity with the negatively charged pyrophosphate moiety.
Biochemical Characterization of Molybdenum Cofactor-free Nitrate Reductase from Neurospora crassa*
TLDR
This work reported the first biochemical characterization of a Moco-free eukaryotic NR from the fungus Neurospora crassa, documenting that Moco is necessary and sufficient to induce dimer formation, and showed that at least in vitro the active site formation of NR is an autonomous process.
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TLDR
The deduced amino acid sequence of higher-plant NR showed that it contained about 900 residues with a predicted molecular size of approximately 100 kD, which may be explained by the runs of acidic residues near the N terminus of well-characterized and sequenced NR forms such as squash.
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