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PDBsum entry 1m1n

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protein ligands metals Protein-protein interface(s) links
Oxidoreductase PDB id
1m1n
Jmol
Contents
Protein chains
477 a.a. *
522 a.a. *
Ligands
HCA ×4
CFN ×4
CLF ×4
Metals
_CA ×4
Waters ×5021
* Residue conservation analysis
PDB id:
1m1n
Name: Oxidoreductase
Title: Nitrogenase mofe protein from azotobacter vinelandii
Structure: Nitrogenase molybdenum-iron protein alpha chain. Chain: a, c, e, g. Synonym: nifd, nitrogenase mofe protein alpha subunit, nitrogenase component i, dinitrogenase. Nitrogenase molybdenum-iron protein beta chain. Chain: b, d, f, h. Synonym: nifk, nitrogenase mofe protein beta subunit, nitrogenase component i, dinitrogenase. Ec: 1.18.6.1
Source: Azotobacter vinelandii. Organism_taxid: 354. Organism_taxid: 354
Biol. unit: Tetramer (from PQS)
Resolution:
1.16Å     R-factor:   0.123     R-free:   0.149
Authors: O.Einsle,F.A.Tezcan,S.L.A.Andrade,B.Schmid,M.Yoshida, J.B.Howard,D.C.Rees
Key ref:
O.Einsle et al. (2002). Nitrogenase MoFe-protein at 1.16 A resolution: a central ligand in the FeMo-cofactor. Science, 297, 1696-1700. PubMed id: 12215645 DOI: 10.1126/science.1073877
Date:
19-Jun-02     Release date:   11-Sep-02    
PROCHECK
Go to PROCHECK summary
 Headers
 References

Protein chains
Pfam   ArchSchema ?
P07328  (NIFD_AZOVI) -  Nitrogenase molybdenum-iron protein alpha chain
Seq:
Struc:
492 a.a.
477 a.a.
Protein chains
Pfam   ArchSchema ?
P07329  (NIFK_AZOVI) -  Nitrogenase molybdenum-iron protein beta chain
Seq:
Struc:
 
Seq:
Struc:
523 a.a.
522 a.a.
Key:    PfamA domain  PfamB domain  Secondary structure  CATH domain

 Enzyme reactions 
   Enzyme class: Chains A, B, C, D, E, F, G, H: E.C.1.18.6.1  - Nitrogenase.
[IntEnz]   [ExPASy]   [KEGG]   [BRENDA]

      Pathway:
Nitrogenase
      Reaction: 8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O = 8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate
8 × reduced ferredoxin
+ 8 × H(+)
+ N(2)
+ 16 × ATP
+ 16 × H(2)O
= 8 × oxidized ferredoxin
+ H(2)
+ 2 × NH(3)
+ 16 × ADP
+ 16 × phosphate
      Cofactor: Iron-sulfur; Vanadium or molybdenum
Iron-sulfur
Vanadium
or molybdenum
Molecule diagrams generated from .mol files obtained from the KEGG ftp site
 Gene Ontology (GO) functional annotation 
  GO annot!
  Cellular component     molybdenum-iron nitrogenase complex   1 term 
  Biological process     oxidation-reduction process   2 terms 
  Biochemical function     nucleotide binding     7 terms  

 

 
    reference    
 
 
DOI no: 10.1126/science.1073877 Science 297:1696-1700 (2002)
PubMed id: 12215645  
 
 
Nitrogenase MoFe-protein at 1.16 A resolution: a central ligand in the FeMo-cofactor.
O.Einsle, F.A.Tezcan, S.L.Andrade, B.Schmid, M.Yoshida, J.B.Howard, D.C.Rees.
 
  ABSTRACT  
 
A high-resolution crystallographic analysis of the nitrogenase MoFe-protein reveals a previously unrecognized ligand coordinated to six iron atoms in the center of the catalytically essential FeMo-cofactor. The electron density for this ligand is masked in structures with resolutions lower than 1.55 angstroms, owing to Fourier series termination ripples from the surrounding iron and sulfur atoms in the cofactor. The central atom completes an approximate tetrahedral coordination for the six iron atoms, instead of the trigonal coordination proposed on the basis of lower resolution structures. The crystallographic refinement at 1.16 angstrom resolution is consistent with this newly detected component being a light element, most plausibly nitrogen. The presence of a nitrogen atom in the cofactor would have important implications for the mechanism of dinitrogen reduction by nitrogenase.
 
  Selected figure(s)  
 
Figure 2.
Fig. 2. Contributions of individual atom types to the resolution-dependent electron density profile in the central cavity of the FeMo-cofactor. Six iron atoms and all nine of the cluster's sulfur atoms are located on two concentric spheres. Having identical distances from the center (3.3 Å for sulfur, 2.0 Å for iron), they are the main contributors to the electron density profile there. The apical iron and molybdenum atoms exert only a minor influence. Plots of (r) versus d[max], calculated analogously to Fig. 1 (inset), illustrate this effect. The curves for six iron atoms at 2.0 Å (blue), nine sulfur atoms at 3.3 Å (dark yellow), and one apical iron (Fe1, gray) and the molybdenum (orange) at 3.5 Å are shown. The sum of of all these contributions is shown in black.
Figure 3.
Fig. 3. Stereo representation of the FeMo-cofactor with the central ligand modeled as a nitrogen atom. The electron density map shown is a weighted 2F[o] F[c] map of the 1.16 Å resolution structure of dithionite-reduced A. vinelandii MoFe-protein contoured at 3 .
 
  The above figures are reprinted by permission from the AAAs: Science (2002, 297, 1696-1700) copyright 2002.  
  Figures were selected by an automated process.  

Literature references that cite this PDB file's key reference

  PubMed id Reference
21841804 A.Pomowski, W.G.Zumft, P.M.Kroneck, and O.Einsle (2011).
N2O binding at a [4Cu:2S] copper-sulphur cluster in nitrous oxide reductase.
  Nature, 477, 234-237.
PDB codes: 3sbp 3sbq 3sbr
21337527 D.L.Ma, D.S.Chan, B.Y.Man, and C.H.Leung (2011).
Oligonucleotide-based luminescent detection of metal ions.
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21393052 E.M.Shepard, E.S.Boyd, J.B.Broderick, and J.W.Peters (2011).
Biosynthesis of complex iron-sulfur enzymes.
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21231969 G.Martínez-Noël, L.Curatti, J.A.Hernandez, and L.M.Rubio (2011).
NifB and NifEN protein levels are regulated by ClpX2 under nitrogen fixation conditions in Azotobacter vinelandii.
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21487574 I.Dance (2011).
How does vanadium nitrogenase reduce CO to hydrocarbons?
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21350172 J.J.Scepaniak, C.S.Vogel, M.M.Khusniyarov, F.W.Heinemann, K.Meyer, and J.M.Smith (2011).
Synthesis, structure, and reactivity of an iron(V) nitride.
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21212358 J.T.Kaiser, Y.Hu, J.A.Wiig, D.C.Rees, and M.W.Ribbe (2011).
Structure of precursor-bound NifEN: a nitrogenase FeMo cofactor maturase/insertase.
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PDB code: 3pdi
21258384 K.Arashiba, Y.Miyake, and Y.Nishibayashi (2011).
A molybdenum complex bearing PNP-type pincer ligands leads to the catalytic reduction of dinitrogen into ammonia.
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21038112 K.Rupnik, Y.Hu, A.W.Fay, M.W.Ribbe, and B.J.Hales (2011).
Variable-temperature, variable-field magnetic circular dichroism spectroscopic study of NifEN-bound precursor and "FeMoco".
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21265773 T.A.Clarke, S.Fairhurst, D.J.Lowe, N.J.Watmough, and R.R.Eady (2011).
Electron transfer and half-reactivity in nitrogenase.
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Bioinspired molecular co-catalysts bonded to a silicon photocathode for solar hydrogen evolution.
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Formation of a homocitrate-free iron-molybdenum cluster on NifEN: implications for the role of homocitrate in nitrogenase assembly.
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20418861 D.W.Mulder, E.S.Boyd, R.Sarma, R.K.Lange, J.A.Endrizzi, J.B.Broderick, and J.W.Peters (2010).
Stepwise [FeFe]-hydrogenase H-cluster assembly revealed in the structure of HydA(DeltaEFG).
  Nature, 465, 248-251.
PDB code: 3lx4
20221528 I.Dance (2010).
Mimicking nitrogenase.
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21104954 M.Hölscher, and W.Leitner (2010).
Lewis acid assisted stabilization of side-on bonded N2 in [Ru(NCN)]-pincer complexes--computational catalyst design directed at NH3 synthesis from N2 and H2.
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20400946 N.Muraki, J.Nomata, K.Ebata, T.Mizoguchi, T.Shiba, H.Tamiaki, G.Kurisu, and Y.Fujita (2010).
X-ray crystal structure of the light-independent protochlorophyllide reductase.
  Nature, 465, 110-114.
PDB codes: 3aek 3aeq 3aer 3aes 3aet 3aeu
20221527 Y.Hu, A.W.Fay, C.C.Lee, J.A.Wiig, and M.W.Ribbe (2010).
Dual functions of NifEN: insights into the evolution and mechanism of nitrogenase.
  Dalton Trans, 39, 2964-2971.  
20030377 Y.Hu, and M.W.Ribbe (2010).
Decoding the nitrogenase mechanism: the homologue approach.
  Acc Chem Res, 43, 475-484.  
19089947 A.M.Burroughs, L.M.Iyer, and L.Aravind (2009).
Natural history of the E1-like superfamily: implication for adenylation, sulfur transfer, and ubiquitin conjugation.
  Proteins, 75, 895-910.  
19578539 A.N.Glazer, and K.J.Kechris (2009).
Conserved amino acid sequence features in the alpha subunits of MoFe, VFe, and FeFe nitrogenases.
  PLoS One, 4, e6136.  
19663502 B.M.Barney, D.Lukoyanov, R.Y.Igarashi, M.Laryukhin, T.C.Yang, D.R.Dean, B.M.Hoffman, and L.C.Seefeldt (2009).
Trapping an intermediate of dinitrogen (N2) reduction on nitrogenase.
  Biochemistry, 48, 9094-9102.  
19458968 B.M.Barney, M.G.Yurth, P.C.Dos Santos, D.R.Dean, and L.C.Seefeldt (2009).
A substrate channel in the nitrogenase MoFe protein.
  J Biol Inorg Chem, 14, 1015-1022.  
19828444 C.C.Lee, M.A.Blank, A.W.Fay, J.M.Yoshizawa, Y.Hu, K.O.Hodgson, B.Hedman, and M.W.Ribbe (2009).
Stepwise formation of P-cluster in nitrogenase MoFe protein.
  Proc Natl Acad Sci U S A, 106, 18474-18478.  
19478062 C.C.Lee, Y.Hu, and M.W.Ribbe (2009).
Unique features of the nitrogenase VFe protein from Azotobacter vinelandii.
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19623393 E.M.Zueva, M.M.Petrova, R.Herchel, Z.Trávnícek, R.G.Raptis, L.Mathivathanan, and J.E.McGrady (2009).
Electronic structure and magnetic properties of a trigonal prismatic Cu(II)6 cluster.
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19675644 G.Schwarz, R.R.Mendel, and M.W.Ribbe (2009).
Molybdenum cofactors, enzymes and pathways.
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Molybdenum trafficking for nitrogen fixation.
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19675641 J.C.Fontecilla-Camps, P.Amara, C.Cavazza, Y.Nicolet, and A.Volbeda (2009).
Structure-function relationships of anaerobic gas-processing metalloenzymes.
  Nature, 460, 814-822.  
19514721 J.M.Yoshizawa, M.A.Blank, A.W.Fay, C.C.Lee, J.A.Wiig, Y.Hu, K.O.Hodgson, B.Hedman, and M.W.Ribbe (2009).
Optimization of FeMoco maturation on NifEN.
  J Am Chem Soc, 131, 9321-9325.  
19234723 K.Hollenstein, M.Comellas-Bigler, L.E.Bevers, M.C.Feiters, W.Meyer-Klaucke, P.L.Hagedoorn, and K.P.Locher (2009).
Distorted octahedral coordination of tungstate in a subfamily of specific binding proteins.
  J Biol Inorg Chem, 14, 663-672.
PDB codes: 3cfx 3cfz 3cg1 3cg3 3cij
19438179 K.P.Chiang, P.M.Barrett, F.Ding, J.M.Smith, S.Kingsley, W.W.Brennessel, M.M.Clark, R.J.Lachicotte, and P.L.Holland (2009).
Ligand dependence of binding to three-coordinate Fe(II) complexes.
  Inorg Chem, 48, 5106-5116.  
19489731 L.C.Seefeldt, B.M.Hoffman, and D.R.Dean (2009).
Mechanism of Mo-dependent nitrogenase.
  Annu Rev Biochem, 78, 701-722.  
19212966 O.Kühl (2009).
If the cluster were a cluster: the active centre of nitrogenase revisited.
  Chembiochem, 10, 809-811.  
19140682 S.Chakraborty, N.S.Nemeria, A.Balakrishnan, G.S.Brandt, M.M.Kneen, A.Yep, M.J.McLeish, G.L.Kenyon, G.A.Petsko, D.Ringe, and F.Jordan (2009).
Detection and time course of formation of major thiamin diphosphate-bound covalent intermediates derived from a chromophoric substrate analogue on benzoylformate decarboxylase.
  Biochemistry, 48, 981-994.
PDB codes: 3f6b 3f6e
19206188 S.Groysman, and R.H.Holm (2009).
Biomimetic chemistry of iron, nickel, molybdenum, and tungsten in sulfur-ligated protein sites.
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19343768 S.Schenk, B.Kirchner, and M.Reiher (2009).
A stable six-coordinate intermediate in ammonia-dinitrogen exchange at Schrock's molybdenum catalyst.
  Chemistry, 15, 5073-5082.  
19805110 Y.Hu, J.M.Yoshizawa, A.W.Fay, C.C.Lee, J.A.Wiig, and M.W.Ribbe (2009).
Catalytic activities of NifEN: implications for nitrogenase evolution and mechanism.
  Proc Natl Acad Sci U S A, 106, 16962-16966.  
18535145 G.J.Workun, K.Moquin, R.A.Rothery, and J.H.Weiner (2008).
Evolutionary persistence of the molybdopyranopterin-containing sulfite oxidase protein fold.
  Microbiol Mol Biol Rev, 72, 228.  
18697927 J.A.Hernandez, L.Curatti, C.P.Aznar, Z.Perova, R.D.Britt, and L.M.Rubio (2008).
Metal trafficking for nitrogen fixation: NifQ donates molybdenum to NifEN/NifH for the biosynthesis of the nitrogenase FeMo-cofactor.
  Proc Natl Acad Sci U S A, 105, 11679-11684.  
18273850 J.Schemberg, K.Schneider, D.Fenske, and A.Müller (2008).
Azotobacter vinelandii metal storage protein: "classical" inorganic chemistry involved in Mo/W uptake and release processes.
  Chembiochem, 9, 595-602.  
18429691 L.M.Rubio, and P.W.Ludden (2008).
Biosynthesis of the iron-molybdenum cofactor of nitrogenase.
  Annu Rev Microbiol, 62, 93.  
18697949 P.C.Dos Santos, and D.R.Dean (2008).
A newly discovered role for iron-sulfur clusters.
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18713389 Q.Cheng (2008).
Perspectives in biological nitrogen fixation research.
  J Integr Plant Biol, 50, 786-798.  
18386899 S.J.George, R.Y.Igarashi, Y.Xiao, J.A.Hernandez, M.Demuez, D.Zhao, Y.Yoda, P.W.Ludden, L.M.Rubio, and S.P.Cramer (2008).
Extended X-ray absorption fine structure and nuclear resonance vibrational spectroscopy reveal that NifB-co, a FeMo-co precursor, comprises a 6Fe core with an interstitial light atom.
  J Am Chem Soc, 130, 5673-5680.  
18813370 S.Romo, N.S.Antonova, J.J.Carbó, and J.M.Poblet (2008).
Influence of polyoxometalate ligands on the nature of high-valent transition metal nitrido species. A theoretical analysis of experimentally known and unprecedented compounds.
  Dalton Trans, (), 5166-5172.  
18578487 V.Pelmenschikov, D.A.Case, and L.Noodleman (2008).
Ligand-bound S = 1/2 FeMo-cofactor of nitrogenase: hyperfine interaction analysis and implication for the central ligand X identity.
  Inorg Chem, 47, 6162-6172.  
18444648 Y.Yu, A.R.Sadique, J.M.Smith, T.R.Dugan, R.E.Cowley, W.W.Brennessel, C.J.Flaschenriem, E.Bill, T.R.Cundari, and P.L.Holland (2008).
The reactivity patterns of low-coordinate iron-hydride complexes.
  J Am Chem Soc, 130, 6624-6638.  
18461203 Z.H.Zhou, C.Y.Chen, Z.X.Cao, K.R.Tsai, and Y.L.Chow (2008).
N-heterocycle chelated oxomolybdenum(VI and V) complexes with bidentate citrate.
  Dalton Trans, (), 2475-2479.  
17521738 A.W.Fay, Y.Hu, B.Schmid, and M.W.Ribbe (2007).
Molecular insights into nitrogenase FeMoco insertion--the role of His 274 and His 451 of MoFe protein alpha subunit.
  J Inorg Biochem, 101, 1630-1641.  
17349817 B.Kirchner, F.Wennmohs, S.Ye, and F.Neese (2007).
Theoretical bioinorganic chemistry: the electronic structure makes a difference.
  Curr Opin Chem Biol, 11, 134-141.  
17660283 C.R.Staples, S.Lahiri, J.Raymond, L.Von Herbulis, B.Mukhophadhyay, and R.E.Blankenship (2007).
Expression and association of group IV nitrogenase NifD and NifH homologs in the non-nitrogen-fixing archaeon Methanocaldococcus jannaschii.
  J Bacteriol, 189, 7392-7398.  
17360611 G.B.Seiffert, G.M.Ullmann, A.Messerschmidt, B.Schink, P.M.Kroneck, and O.Einsle (2007).
Structure of the non-redox-active tungsten/[4Fe:4S] enzyme acetylene hydratase.
  Proc Natl Acad Sci U S A, 104, 3073-3077.
PDB code: 2e7z
17508082 G.Periyasamy, M.Sundararajan, I.H.Hillier, N.A.Burton, and J.J.McDouall (2007).
The binding of nitric oxide at the Cu(i) site of copper nitrite reductase and of inorganic models: DFT calculations of the energetics and EPR parameters of side-on and end-on structures.
  Phys Chem Chem Phys, 9, 2498-2506.  
17340220 H.Sakurai, and H.Masukawa (2007).
Promoting R & D in photobiological hydrogen production utilizing mariculture-raised cyanobacteria.
  Mar Biotechnol (NY), 9, 128-145.  
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Elucidating the coordination chemistry and mechanism of biological nitrogen fixation.
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17163967 J.A.Hernandez, R.Y.Igarashi, B.Soboh, L.Curatti, D.R.Dean, P.W.Ludden, and L.M.Rubio (2007).
NifX and NifEN exchange NifB cofactor and the VK-cluster, a newly isolated intermediate of the iron-molybdenum cofactor biosynthetic pathway.
  Mol Microbiol, 63, 177-192.  
17198413 J.Vela, J.Cirera, J.M.Smith, R.J.Lachicotte, C.J.Flaschenriem, S.Alvarez, and P.L.Holland (2007).
Quantitative geometric descriptions of the belt iron atoms of the iron-molybdenum cofactor of nitrogenase and synthetic iron(II) model complexes.
  Inorg Chem, 46, 60-71.  
17978192 L.Curatti, J.A.Hernandez, R.Y.Igarashi, B.Soboh, D.Zhao, and L.M.Rubio (2007).
In vitro synthesis of the iron-molybdenum cofactor of nitrogenase from iron, sulfur, molybdenum, and homocitrate using purified proteins.
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17704896 M.J.Russell (2007).
The alkaline solution to the emergence of life: energy, entropy and early evolution.
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17892284 M.L.Hlavinka, T.Miyaji, R.J.Staples, and R.H.Holm (2007).
Hydroxide-promoted core conversions of molybdenum-iron-sulfur edge-bridged double cubanes: oxygen-ligated topological PN clusters.
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17285558 M.L.McKee (2007).
Modeling hydrogen evolution from the Fe4S4 and Fe8S9X (X = N, C) clusters. Can a Fe--S high-spin cluster serve as a surrogate for the FeMo cofactor?
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17318945 M.L.McKee (2007).
Modeling the nitrogenase FeMo cofactor with high-spin Fe8S9X+ (X=N, C) clusters. Is the first step for N2 reduction to NH3 a concerted dihydrogen transfer?
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17717179 P.Avenier, M.Taoufik, A.Lesage, X.Solans-Monfort, A.Baudouin, A.de Mallmann, L.Veyre, J.M.Basset, O.Eisenstein, L.Emsley, and E.A.Quadrelli (2007).
Dinitrogen dissociation on an isolated surface tantalum atom.
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17610955 P.C.Dos Santos, S.M.Mayer, B.M.Barney, L.C.Seefeldt, and D.R.Dean (2007).
Alkyne substrate interaction within the nitrogenase MoFe protein.
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17279830 R.P.Pesavento, C.P.Berlinguette, and R.H.Holm (2007).
Stabilization of reduced molybdenum-iron-sulfur single- and double-cubane clusters by cyanide ligation.
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17898892 R.R.Mendel, A.G.Smith, A.Marquet, and M.J.Warren (2007).
Metal and cofactor insertion.
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17563349 Y.Hu, A.W.Fay, C.C.Lee, and M.W.Ribbe (2007).
P-cluster maturation on nitrogenase MoFe protein.
  Proc Natl Acad Sci U S A, 104, 10424-10429.  
17203313 Y.Hu, A.W.Fay, and M.W.Ribbe (2007).
Molecular insights into nitrogenase FeMo cofactor insertion: the role of His 362 of the MoFe protein alpha subunit in FeMo cofactor incorporation.
  J Biol Inorg Chem, 12, 449-460.  
17088552 B.M.Barney, D.Lukoyanov, T.C.Yang, D.R.Dean, B.M.Hoffman, and L.C.Seefeldt (2006).
A methyldiazene (HN=N-CH3)-derived species bound to the nitrogenase active-site FeMo cofactor: Implications for mechanism.
  Proc Natl Acad Sci U S A, 103, 17113-17118.  
16688314 B.M.Barney, H.I.Lee, P.C.Dos Santos, B.M.Hoffman, D.R.Dean, and L.C.Seefeldt (2006).
Breaking the N2 triple bond: insights into the nitrogenase mechanism.
  Dalton Trans, (), 2277-2284.  
16764020 C.Herrmann, L.Yu, and M.Reiher (2006).
Spin states in polynuclear clusters: the [Fe2O2] core of the methane monooxygenase active site.
  J Comput Chem, 27, 1223-1239.  
16786542 F.Studt, and F.Tuczek (2006).
Theoretical, spectroscopic, and mechanistic studies on transition-metal dinitrogen complexes: implications to reactivity and relevance to the nitrogenase problem.
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16983726 H.J.Himmel, and M.Reiher (2006).
Intrinsic dinitrogen activation at bare metal atoms.
  Angew Chem Int Ed Engl, 45, 6264-6288.  
17088547 J.B.Howard, and D.C.Rees (2006).
How many metals does it take to fix N2? A mechanistic overview of biological nitrogen fixation.
  Proc Natl Acad Sci U S A, 103, 17088-17093.  
16510305 J.W.Peters, and R.K.Szilagyi (2006).
Exploring new frontiers of nitrogenase structure and mechanism.
  Curr Opin Chem Biol, 10, 101-108.  
17009470 K.Fisher, D.J.Lowe, and J.Petersen (2006).
Vanadium (V) is reduced by the 'as isolated' nitrogenase Fe-protein at neutral pH.
  Chem Commun (Camb), (), 2807-2809.  
16518789 K.Muñiz, and M.Nieger (2006).
Catalytic activation of N-N multiple bonds: a homogeneous palladium catalyst for mechanistically unprecedented reduction of azo compounds.
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16567617 L.Curatti, P.W.Ludden, and L.M.Rubio (2006).
NifB-dependent in vitro synthesis of the iron-molybdenum cofactor of nitrogenase.
  Proc Natl Acad Sci U S A, 103, 5297-5301.  
16830148 L.Noodleman, and W.G.Han (2006).
Structure, redox, pKa, spin. A golden tetrad for understanding metalloenzyme energetics and reaction pathways.
  J Biol Inorg Chem, 11, 674-694.  
17050697 L.P.Spencer, B.A.MacKay, B.O.Patrick, and M.D.Fryzuk (2006).
Inner-sphere two-electron reduction leads to cleavage and functionalization of coordinated dinitrogen.
  Proc Natl Acad Sci U S A, 103, 17094-17098.  
16423898 M.C.Corbett, Y.Hu, A.W.Fay, M.W.Ribbe, B.Hedman, and K.O.Hodgson (2006).
Structural insights into a protein-bound iron-molybdenum cofactor precursor.
  Proc Natl Acad Sci U S A, 103, 1238-1243.  
17176061 M.H.Sazinsky, P.W.Dunten, M.S.McCormick, A.DiDonato, and S.J.Lippard (2006).
X-ray structure of a hydroxylase-regulatory protein complex from a hydrocarbon-oxidizing multicomponent monooxygenase, Pseudomonas sp. OX1 phenol hydroxylase.
  Biochemistry, 45, 15392-15404.
PDB codes: 2inn 2inp
16858715 M.V.Bennett, and R.H.Holm (2006).
Self-assembly of a tetradecanuclear iron nitride cluster.
  Angew Chem Int Ed Engl, 45, 5613-5616.  
17083217 N.C.Smythe, R.R.Schrock, P.Müller, and W.W.Weare (2006).
Synthesis of [(HIPTNCH2CH2)3N]V compounds (HIPT = 3,5-(2,4,6-i-Pr3C6H2)2C6H3) and an evaluation of vanadium for the reduction of dinitrogen to ammonia.
  Inorg Chem, 45, 9197-9205.  
16788911 R.K.Szilagyi, and M.A.Winslow (2006).
On the accuracy of density functional theory for iron-sulfur clusters.
  J Comput Chem, 27, 1385-1397.  
17083216 W.W.Weare, R.R.Schrock, A.S.Hock, and P.Müller (2006).
Synthesis of molybdenum complexes that contain "hybrid" triamidoamine ligands, [(hexaisopropylterphenyl-NCH2CH2)2NCH2CH2N-aryl]3-, and studies relevant to catalytic reduction of dinitrogen.
  Inorg Chem, 45, 9185-9196.  
17085586 W.W.Weare, X.Dai, M.J.Byrnes, J.M.Chin, R.R.Schrock, and P.Müller (2006).
Catalytic reduction of dinitrogen to ammonia at a single molybdenum center.
  Proc Natl Acad Sci U S A, 103, 17099-17106.  
17050696 Y.Hu, M.C.Corbett, A.W.Fay, J.A.Webber, K.O.Hodgson, B.Hedman, and M.W.Ribbe (2006).
FeMo cofactor maturation on NifEN.
  Proc Natl Acad Sci U S A, 103, 17119-17124.  
17062756 Y.Hu, M.C.Corbett, A.W.Fay, J.A.Webber, K.O.Hodgson, B.Hedman, and M.W.Ribbe (2006).
Nitrogenase Fe protein: A molybdate/homocitrate insertase.
  Proc Natl Acad Sci U S A, 103, 17125-17130.  
15551315 B.Kirchner, M.Reiher, A.Hille, J.Hutter, and B.A.Hess (2005).
Car-Parrinello molecular dynamics study of the initial dinitrogen reduction step in Sellmann-type nitrogenase model complexes.
  Chemistry, 11, 574-583.  
15651045 D.Fenske, M.Gnida, K.Schneider, W.Meyer-Klaucke, J.Schemberg, V.Henschel, A.K.Meyer, A.Knöchel, and A.Müller (2005).
A new type of metalloprotein: The Mo storage protein from azotobacter vinelandii contains a polynuclear molybdenum-oxide cluster.
  Chembiochem, 6, 405-413.  
16342309 F.Neese (2005).
The Yandulov/Schrock cycle and the nitrogenase reaction: pathways of nitrogen fixation studied by density functional theory.
  Angew Chem Int Ed Engl, 45, 196-199.  
16086351 F.Studt, and F.Tuczek (2005).
Energetics and mechanism of a room-temperature catalytic process for ammonia synthesis (Schrock cycle): comparison with biological nitrogen fixation.
  Angew Chem Int Ed Engl, 44, 5639-5642.  
15782259 J.Han, and D.Coucouvanis (2005).
Synthesis and structure of the organometallic MFe2(mu3-S)2 clusters (M = Mo or Fe).
  Dalton Trans, (), 1234-1240.  
16013077 J.Kästner, and P.E.Blöchl (2005).
Towards an understanding of the workings of nitrogenase from DFT calculations.
  Chemphyschem, 6, 1724-1726.  
16229569 J.Kästner, S.Hemmen, and P.E.Blöchl (2005).
Activation and protonation of dinitrogen at the FeMo cofactor of nitrogenase.
  J Chem Phys, 123, 074306.  
15629911 L.M.Rubio, and P.W.Ludden (2005).
Maturation of nitrogenase: a biochemical puzzle.
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16359167 R.R.Schrock (2005).
Catalytic reduction of dinitrogen to ammonia at a single molybdenum center.
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15728375 Y.Hu, A.W.Fay, and M.W.Ribbe (2005).
Identification of a nitrogenase FeMo cofactor precursor on NifEN complex.
  Proc Natl Acad Sci U S A, 102, 3236-3241.  
16166259 Y.Hu, M.C.Corbett, A.W.Fay, J.A.Webber, B.Hedman, K.O.Hodgson, and M.W.Ribbe (2005).
Nitrogenase reactivity with P-cluster variants.
  Proc Natl Acad Sci U S A, 102, 13825-13830.  
15887041 Z.Maskos, K.Fisher, M.Sørlie, W.E.Newton, and B.J.Hales (2005).
Variant MoFe proteins of Azotobacter vinelandii: effects of carbon monoxide on electron paramagnetic resonance spectra generated during enzyme turnover.
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15127437 B.Zheng, J.D.Tice, L.S.Roach, and R.F.Ismagilov (2004).
A droplet-based, composite PDMS/glass capillary microfluidic system for evaluating protein crystallization conditions by microbatch and vapor-diffusion methods with on-chip X-ray diffraction.
  Angew Chem Int Ed Engl, 43, 2508-2511.  
15540264 J.K.Padden Metzker, and J.E.McGrady (2004).
An electronic perspective on the reduction of an n=n double bond at a conserved dimolybdenum core.
  Chemistry, 10, 6447-6455.  
15298939 J.L.Liao, and D.N.Beratan (2004).
How does protein architecture facilitate the transduction of ATP chemical-bond energy into mechanical work? The cases of nitrogenase and ATP binding-cassette proteins.
  Biophys J, 87, 1369-1377.  
15263897 R.Dixon, and D.Kahn (2004).
Genetic regulation of biological nitrogen fixation.
  Nat Rev Microbiol, 2, 621-631.  
14718917 S.C.Harrison (2004).
Whither structural biology?
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12657732 H.B.Gray (2003).
Biological inorganic chemistry at the beginning of the 21st century.
  Proc Natl Acad Sci U S A, 100, 3563-3568.  
12642670 S.C.Lee, and R.H.Holm (2003).
Speculative synthetic chemistry and the nitrogenase problem.
  Proc Natl Acad Sci U S A, 100, 3595-3600.  
The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB codes are shown on the right.