DB code: M00199

RLCP classification 10.22025.100.10765 : Electron transfer
1.15.8230.352 : Hydrolysis
10.25130.110.10590 : Electron transfer
CATH domain 3.40.50.1980 : Rossmann fold Catalytic domain
3.40.50.1980 : Rossmann fold Catalytic domain
3.40.50.1980 : Rossmann fold Catalytic domain
3.40.50.1980 : Rossmann fold Catalytic domain
3.40.50.1980 : Rossmann fold
3.40.50.1980 : Rossmann fold
1.20.89.10 : Nitrogenase Molybdenum-iron Protein, subunit B; domain 4
3.40.50.300 : Rossmann fold Catalytic domain
E.C. 1.18.6.1
CSA
M-CSA
MACiE

CATH domain Related DB codes (homologues)
1.20.89.10 : Nitrogenase Molybdenum-iron Protein, subunit B; domain 4 M00114
3.40.50.1980 : Rossmann fold M00114
3.40.50.300 : Rossmann fold S00527 S00547 S00548 S00550 S00554 S00555 S00671 S00672 S00676 S00680 S00682 S00913 S00914 S00301 S00302 S00303 S00304 S00307 S00308 S00305 S00306 S00309 S00310 S00311 M00114 D00129 D00130 D00540 M00186

Uniprot Enzyme Name
UniprotKB Protein name Synonyms Pfam
P00467 Nitrogenase molybdenum-iron protein alpha chain
EC 1.18.6.1
Nitrogenase component I
Dinitrogenase
PF00148 (Oxidored_nitro)
[Graphical View]
P11347 Nitrogenase molybdenum-iron protein beta chain
EC 1.18.6.1
Nitrogenase component I
Dinitrogenase
PF00148 (Oxidored_nitro)
[Graphical View]
P00456 Nitrogenase iron protein 1
EC 1.18.6.1
Nitrogenase component II
Nitrogenase Fe protein 1
Nitrogenase reductase
PF00142 (Fer4_NifH)
[Graphical View]

KEGG enzyme name
nitrogenase

UniprotKB: Accession Number Entry name Activity Subunit Subcellular location Cofactor
P00467 NIFD_CLOPA 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. Tetramer of two alpha and two beta chains. Forms complex with the iron protein (nitrogenase component 2). Binds 1 8Fe-7S cluster per heterodimer (By similarity). Binds 1 7Fe-Mo-9S-X-homocitryl cluster per subunit. The identity of the X atom is not known, possibly carbon or oxygen (By similarity).
P11347 NIFK_CLOPA 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. Tetramer of two alpha and two beta chains. Forms complex with the iron protein (nitrogenase component 2). Binds 1 8Fe-7S cluster per heterodimer.
P00456 NIFH1_CLOPA 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. Homodimer. Binds 1 4Fe-4S cluster per dimer.

KEGG Pathways
Map code Pathways E.C.
MAP00625 Tetrachloroethene degradation
MAP00910 Nitrogen metabolism

Compound table
Cofactors Substrates Products Intermediates
KEGG-id L00026 L00025 C01251 L00024 C00305 C00138 C00080 C00697 C00002 C00001 C00139 C00014 C00008 C00009
E.C.
Compound [8Fe-7S](P cluster) [7Fe-9S-Mo](FeMoco) Homocitrate [4Fe-4S] Magnesium Reduced ferredoxin H+ N2 ATP H2O Oxidized ferredoxin NH3 ADP Orthophosphate Transition-state for ATP hydrolysis Intermediate for Nitrogenation
Type heavy metal,sulfide group heavy metal,sulfide group carbohydrate,carboxyl group heavy metal,sulfide group divalent metal (Ca2+, Mg2+) heavy metal,peptide/protein,sulfide group others others amine group,nucleotide H2O heavy metal,peptide/protein,sulfide group amine group,organic ion amine group,nucleotide phosphate group/phosphate ion
ChEBI 48796
48796
52222
52222
33725
33725
18420
18420
15378
15378
17997
17997
15422
15422
15377
15377
16134
16134
16761
16761
26078
26078
PubChem 439459
439459
888
888
1038
1038
947
947
5957
5957
22247451
962
22247451
962
222
222
6022
6022
1004
22486802
1004
22486802
1mioA01 Unbound Bound:CFM Bound:HCA Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioC01 Unbound Bound:CFM Bound:HCA Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioA02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioC02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioA03 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioC03 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioB01 Analogue:CLP Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioD01 Analogue:CLP Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioB02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioD02 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioB04 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioD04 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioB03 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1mioD03 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1cp2A Unbound Unbound Unbound Bound:SF4 Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound
1cp2B Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound Unbound

Reference for Active-site residues
resource references E.C.

Active-site residues
PDB Catalytic residues Cofactor-binding residues Modified residues Main-chain involved in catalysis Comment
1mioA01 CYS 53 CYS 53(P cluster);ILE 465;HIS 482(Homocitrate);HIS 482(FeMoco)
1mioC01 CYS 53 CYS 53(P cluster);ILE 465;HIS 482(Homocitrate);HIS 482(FeMoco)
1mioA02 GLN 182 GLN 182(Homocitrate);CYS 79;CYS 145(P cluster)
1mioC02 GLN 182 GLN 182(Homocitrate);CYS 79;CYS 145(P cluster)
1mioA03 CYS 262(FeMoco)
1mioC03 CYS 262(FeMoco)
1mioB01 CYS 106;THR 110 CYS 23;CYS 48;CYS 106;SER 141(P cluster)
1mioD01 CYS 106;THR 110 CYS 23;CYS 48;CYS 106;SER 141(P cluster)
1mioB02
1mioD02
1mioB04
1mioD04
1mioB03
1mioD03
1cp2A LYS 9;LYS 14;ASP 38;LYS 40;ASP 126 CYS 94;CYS 129(4Fe-4S binding);SER 15(Magnesium binding) GLY 11
1cp2B LYS 9;LYS 14;ASP 38;LYS 40;ASP 126 CYS 94;CYS 129(4Fe-4S binding);SER 15(Magnesium binding) GLY 11

References for Catalytic Mechanism
References Sections No. of steps in catalysis
[5]
Fig.2
[12]
Scheme 1, Scheme 2, Scheme 3
[14]
p.1680-1681
[16]
p.1657-1658
[17]
p.994
[18]
Fig.9, p.347-349
[20]
p.7112-7113
[24]
Fig.2, Fig.3, p.794
[33]
p.27012-27013
[35]
p.10722
[36]
p.13115-13117
[40]
p.16774-16775
[41]
p.9431-9432
[42]
p.15660-15661
[46]
Scheme 1, p.12981-12982
[47]
Fig.2, Fig.4
[50]
p.374-375
[52]
p.11381-11383
[53]
p.404-406
[64]
p.881-886
[68]
p.14750-14751
[71]
p.563-564
[73]
Scheme 1, Scheme 2, Fig.3, Fig.4, p.571-575
[74]
p.13824
[75]
p.648-650
[78]
[81]
Fig.6
[86]
Fig.7, Fig.8
[87]
Fig.5, p.1698-1699
[89]
Scheme 1, Scheme 2, Scheme 3, Scheme 4
[91]
p.1032-1033
[93]
p.380-381
[94]
Fig.3
[95]
Fig.8, p.1048-1051

References
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Resource
Comments
Medline ID
PubMed ID 6246963
Journal Biochim Biophys Acta
Year 1980
Volume 623
Pages 124-38
Authors Huynh BH, Henzl MT, Christner JA, Zimmermann R, Orme-Johnson WH, Munck E
Title Nitrogenase XII. Mossbauer studies of the MoFe protein from Clostridium pasteurianum W5.
Related PDB
Related UniProtKB
[2]
Resource
Comments
Medline ID
PubMed ID 6938202
Journal Biochem Biophys Res Commun
Year 1981
Volume 98
Pages 43-50
Authors Meyer J, Zaccai G
Title Neutron small angle scattering of the Mo-Fe protein (nitrogenase) from Clostridium pasteurianum.
Related PDB
Related UniProtKB
[3]
Resource
Comments
Medline ID
PubMed ID 6948813
Journal J Biol Chem
Year 1982
Volume 257
Pages 1221-3
Authors Yamane T, Weininger MS, Mortenson LE, Rossmann MG
Title Molecular symmetry of the MoFe protein of nitrogenase. Structural homology/nitrogen fixation/x-ray crystallography.
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Related UniProtKB
[4]
Resource
Comments
Medline ID
PubMed ID 6952190
Journal Proc Natl Acad Sci U S A
Year 1982
Volume 79
Pages 378-80
Authors Weininger MS, Mortenson LE
Title Crystallographic properties of the MoFe proteins of nitrogenase from Clostridium pasteurianum and Azotobacter vinelandii.
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Related UniProtKB
[5]
Resource
Comments
Medline ID
PubMed ID 3890886
Journal Annu Rev Biophys Biophys Chem
Year 1985
Volume 14
Pages 419-59
Authors Orme-Johnson WH
Title Molecular basis of biological nitrogen fixation.
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Related UniProtKB
[6]
Resource
Comments
Medline ID
PubMed ID 2840948
Journal Biochemistry
Year 1988
Volume 27
Pages 2800-10
Authors Wang SZ, Chen JS, Johnson JL
Title Distinct structural features of the alpha and beta subunits of nitrogenase molybdenum-iron protein of Clostridium pasteurianum: an analysis of amino acid sequences.
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Related UniProtKB
[7]
Resource
Comments
Medline ID
PubMed ID 2842451
Journal J Inorg Biochem
Year 1988
Volume 33
Pages 111-20
Authors Morgan TV, Mortenson LE, McDonald JW, Watt GD
Title Comparison of redox and EPR properties of the molybdenum iron proteins of Clostridium pasteurianum and Azotobacter vinelandii nitrogenases.
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Related UniProtKB
[8]
Resource
Comments
Medline ID
PubMed ID 2847787
Journal Biochemistry
Year 1988
Volume 27
Pages 6150-6
Authors Meyer J, Gaillard J, Moulis JM
Title Hydrogen-1 nuclear magnetic resonance of the nitrogenase iron protein (Cp2) from Clostridium pasteurianum.
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Related UniProtKB
[9]
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Comments
Medline ID
PubMed ID 2554893
Journal Biochem J
Year 1989
Volume 262
Pages 349-52
Authors George GN, Bare RE, Jin HY, Stiefel EI, Prince RC
Title E.p.r.-spectroscopic studies on the molybdenum-iron site of nitrogenase from Clostridium pasteurianum.
Related PDB
Related UniProtKB
[10]
Resource
Comments
Medline ID
PubMed ID 2153269
Journal Nature
Year 1990
Volume 343
Pages 188-90
Authors Scott DJ, May HD, Newton WE, Brigle KE, Dean DR
Title Role for the nitrogenase MoFe protein alpha-subunit in FeMo-cofactor binding and catalysis.
Related PDB
Related UniProtKB
[11]
Resource
Comments
Medline ID
PubMed ID 2159783
Journal Biochemistry
Year 1990
Volume 29
Pages 3077-82
Authors Morgan TV, McCracken J, Orme-Johnson WH, Mims WB, Mortenson LE, Peisach J
Title Pulsed electron paramagnetic resonance studies of the interaction of Mg-ATP and D2O with the iron protein of nitrogenase.
Related PDB
Related UniProtKB
[12]
Resource
Comments
Medline ID
PubMed ID 1555570
Journal Eur J Biochem
Year 1992
Volume 205
Pages 1-15
Authors Smith BE, Eady RR
Title Metalloclusters of the nitrogenases.
Related PDB
Related UniProtKB
[13]
Resource
Comments X-RAY CRYSTALLOGRAPHY (2.7 ANGSTROMS)
Medline ID
PubMed ID
Journal Nature
Year 1992
Volume 360
Pages 553-60
Authors Kim J, Rees DC
Title Crystallographic structure and functional implications of the nitrogenase molybdenum-iron protein from Azotobacter vinelandii.
Related PDB
Related UniProtKB P07328 P07329
[14]
Resource
Comments
Medline ID
PubMed ID 1529354
Journal Science
Year 1992
Volume 257
Pages 1677-82
Authors Kim J, Rees DC
Title Structural models for the metal centers in the nitrogenase molybdenum-iron protein.
Related PDB
Related UniProtKB
[15]
Resource
Comments
Medline ID
PubMed ID 1740419
Journal J Biol Chem
Year 1992
Volume 267
Pages 3667-73
Authors Wolle D, Kim C, Dean D, Howard JB
Title Ionic interactions in the nitrogenase complex. Properties of Fe-protein containing substitutions for Arg-100.
Related PDB
Related UniProtKB
[16]
Resource
Comments X-RAY CRYSTALLOGRAPHY (2.9 ANGSTROMS).
Medline ID 92410322
PubMed ID 1529353
Journal Science
Year 1992
Volume 257
Pages 1653-9
Authors Georgiadis MM, Komiya H, Chakrabarti P, Woo D, Kornuc JJ, Rees DC
Title Crystallographic structure of the nitrogenase iron protein from Azotobacter vinelandii.
Related PDB 1nip
Related UniProtKB P00459
[17]
Resource
Comments
Medline ID
PubMed ID 1359643
Journal Science
Year 1992
Volume 258
Pages 992-5
Authors Wolle D, Dean DR, Howard JB
Title Nucleotide-iron-sulfur cluster signal transduction in the nitrogenase iron-protein: the role of Asp125.
Related PDB
Related UniProtKB
[18]
Resource
Comments
Medline ID
PubMed ID 8322617
Journal Adv Enzymol Relat Areas Mol Biol
Year 1993
Volume 67
Pages 299-374
Authors Mortenson LE, Seefeldt LC, Morgan TV, Bolin JT
Title The role of metal clusters and MgATP in nitrogenase catalysis.
Related PDB
Related UniProtKB
[19]
Resource
Comments
Medline ID
PubMed ID 8392330
Journal Biochem J
Year 1993
Volume 293
Pages 101-7
Authors Pau RN, Eldridge ME, Lowe DJ, Mitchenall LA, Eady RR
Title Molybdenum-independent nitrogenases of Azotobacter vinelandii: a functional species of alternative nitrogenase-3 isolated from a molybdenum-tolerant strain contains an iron-molybdenum cofactor.
Related PDB
Related UniProtKB
[20]
Resource
Comments X-RAY CRYSTALLOGRAPHY (3.0 ANGSTROMS
Medline ID 93344379
PubMed ID 8393705
Journal Biochemistry
Year 1993
Volume 32
Pages 7104-15
Authors Kim J, Woo D, Rees DC
Title X-ray crystal structure of the nitrogenase molybdenum-iron protein from Clostridium pasteurianum at 3.0-A resolution.
Related PDB 1mio
Related UniProtKB P00467 P11347
[21]
Resource
Comments
Medline ID
PubMed ID 8389587
Journal Biochemistry
Year 1993
Volume 32
Pages 6058-64
Authors Oliver ME, Hales BJ
Title Using dysprosium complexes to probe the nitrogenase paramagnetic centers.
Related PDB
Related UniProtKB
[22]
Resource
Comments
Medline ID
PubMed ID 8440368
Journal FEBS Lett
Year 1993
Volume 318
Pages 118-24
Authors Gerloff DL, Jenny TF, Knecht LJ, Gonnet GH, Benner SA
Title The nitrogenase MoFe protein. A secondary structure prediction.
Related PDB
Related UniProtKB
[23]
Resource
Comments
Medline ID
PubMed ID 8430077
Journal Proc Natl Acad Sci U S A
Year 1993
Volume 90
Pages 1078-82
Authors Bolin JT, Ronco AE, Morgan TV, Mortenson LE, Xuong NH
Title The unusual metal clusters of nitrogenase: structural features revealed by x-ray anomalous diffraction studies of the MoFe protein from Clostridium pasteurianum.
Related PDB
Related UniProtKB
[24]
Resource
Comments
Medline ID
PubMed ID 8484118
Journal Science
Year 1993
Volume 260
Pages 792-4
Authors Chan MK, Kim J, Rees DC
Title The nitrogenase FeMo-cofactor and P-cluster pair: 2.2 A resolution structures.
Related PDB
Related UniProtKB
[25]
Resource
Comments
Medline ID
PubMed ID 8140948
Journal Adv Inorg Biochem
Year 1994
Volume 9
Pages 219-43
Authors Clague MJ, Butler A
Title Functional mimics of vanadium enzymes.
Related PDB
Related UniProtKB
[26]
Resource
Comments
Medline ID
PubMed ID 7918402
Journal Biochemistry
Year 1994
Volume 33
Pages 11842-9
Authors Gavini N, Ma L, Watt G, Burgess BK
Title Purification and characterization of a FeMo cofactor-deficient MoFe protein.
Related PDB
Related UniProtKB
[27]
Resource
Comments
Medline ID
PubMed ID 8106367
Journal J Biol Chem
Year 1994
Volume 269
Pages 3290-4
Authors Chen L, Gavini N, Tsuruta H, Eliezer D, Burgess BK, Doniach S, Hodgson KO
Title MgATP-induced conformational changes in the iron protein from Azotobacter vinelandii, as studied by small-angle x-ray scattering.
Related PDB
Related UniProtKB
[28]
Resource
Comments
Medline ID
PubMed ID 7961744
Journal J Biol Chem
Year 1994
Volume 269
Pages 28076-83
Authors Peters JW, Fisher K, Dean DR
Title Identification of a nitrogenase protein-protein interaction site defined by residues 59 through 67 within the Azotobacter vinelandii Fe protein.
Related PDB
Related UniProtKB
[29]
Resource
Comments
Medline ID
PubMed ID 8034623
Journal J Biol Chem
Year 1994
Volume 269
Pages 18723-6
Authors Zheng L, Dean DR
Title Catalytic formation of a nitrogenase iron-sulfur cluster.
Related PDB
Related UniProtKB
[30]
Resource
Comments
Medline ID
PubMed ID 7703853
Journal Protein Sci
Year 1994
Volume 3
Pages 2073-81
Authors Seefeldt LC
Title Docking of nitrogenase iron- and molybdenum-iron proteins for electron transfer and MgATP hydrolysis: the role of arginine 140 and lysine 143 of the Azotobacter vinelandii iron protein.
Related PDB
Related UniProtKB
[31]
Resource
Comments
Medline ID
PubMed ID 8561464
Journal Annu Rev Microbiol
Year 1995
Volume 49
Pages 335-66
Authors Peters JW, Fisher K, Dean DR
Title Nitrogenase structure and function: a biochemical-genetic perspective.
Related PDB
Related UniProtKB
[32]
Resource
Comments
Medline ID
PubMed ID 7893691
Journal Biochemistry
Year 1995
Volume 34
Pages 2798-808
Authors Kim CH, Newton WE, Dean DR
Title Role of the MoFe protein alpha-subunit histidine-195 residue in FeMo-cofactor binding and nitrogenase catalysis.
Related PDB
Related UniProtKB
[33]
Resource
Comments
Medline ID
PubMed ID 7592949
Journal J Biol Chem
Year 1995
Volume 270
Pages 27007-13
Authors Peters JW, Fisher K, Newton WE, Dean DR
Title Involvement of the P cluster in intramolecular electron transfer within the nitrogenase MoFe protein.
Related PDB
Related UniProtKB
[34]
Resource
Comments
Medline ID
PubMed ID 7495793
Journal Biochemistry
Year 1995
Volume 34
Pages 15646-53
Authors Lanzilotta WN, Holz RC, Seefeldt LC
Title Proton NMR investigation of the [4Fe--4S]1+ cluster environment of nitrogenase iron protein from Azotobacter vinelandii: defining nucleotide-induced conformational changes.
Related PDB
Related UniProtKB
[35]
Resource
Comments
Medline ID
PubMed ID 7662655
Journal Biochemistry
Year 1995
Volume 34
Pages 10713-23
Authors Lanzilotta WN, Ryle MJ, Seefeldt LC
Title Nucleotide hydrolysis and protein conformational changes in Azotobacter vinelandii nitrogenase iron protein: defining the function of aspartate 129.
Related PDB
Related UniProtKB
[36]
Resource
Comments
Medline ID
PubMed ID 7768906
Journal J Biol Chem
Year 1995
Volume 270
Pages 13112-7
Authors Ryle MJ, Lanzilotta WN, Mortenson LE, Watt GD, Seefeldt LC
Title Evidence for a central role of lysine 15 of Azotobacter vinelandii nitrogenase iron protein in nucleotide binding and protein conformational changes.
Related PDB
Related UniProtKB
[37]
Resource
Comments
Medline ID
PubMed ID 8555217
Journal Biochemistry
Year 1996
Volume 35
Pages 472-8
Authors Blanchard CZ, Hales BJ
Title Isolation of two forms of the nitrogenase VFe protein from Azotobacter vinelandii.
Related PDB
Related UniProtKB
[38]
Resource
Comments
Medline ID
PubMed ID 8679547
Journal Biochemistry
Year 1996
Volume 35
Pages 7188-96
Authors Lanzilotta WN, Fisher K, Seefeldt LC
Title Evidence for electron transfer from the nitrogenase iron protein to the molybdenum-iron protein without MgATP hydrolysis: characterization of a tight protein-protein complex.
Related PDB
Related UniProtKB
[39]
Resource
Comments
Medline ID
PubMed ID 8988014
Journal Biochemistry
Year 1996
Volume 35
Pages 16770-6
Authors Lanzilotta WN, Seefeldt LC
Title Electron transfer from the nitrogenase iron protein to the [8Fe-(7/8)S] clusters of the molybdenum-iron protein.
Related PDB
Related UniProtKB
[40]
Resource
Comments
Medline ID
PubMed ID 8555218
Journal Biochemistry
Year 1996
Volume 35
Pages 479-87
Authors Tittsworth RC, Hales BJ
Title Oxidative titration of the nitrogenase VFe protein from Azotobacter vinelandii: an example of redox-gated electron flow.
Related PDB
Related UniProtKB
[41]
Resource
Comments
Medline ID
PubMed ID 8755721
Journal Biochemistry
Year 1996
Volume 35
Pages 9424-34
Authors Ryle MJ, Lanzilotta WN, Seefeldt LC
Title Elucidating the mechanism of nucleotide-dependent changes in the redox potential of the [4Fe-4S] cluster in nitrogenase iron protein: the role of phenylalanine 135.
Related PDB
Related UniProtKB
[42]
Resource
Comments
Medline ID
PubMed ID 8961928
Journal Biochemistry
Year 1996
Volume 35
Pages 15654-62
Authors Ryle MJ, Seefeldt LC
Title The [4Fe-4S] cluster domain of the nitrogenase iron protein facilitates conformational changes required for the cooperative binding of two nucleotides.
Related PDB
Related UniProtKB
[43]
Resource
Comments
Medline ID
PubMed ID 8664266
Journal Biochemistry
Year 1996
Volume 35
Pages 4766-75
Authors Ryle MJ, Seefeldt LC
Title Elucidation of a MgATP signal transduction pathway in the nitrogenase iron protein: formation of a conformation resembling the MgATP-bound state by protein engineering.
Related PDB
Related UniProtKB
[44]
Resource
Comments
Medline ID
PubMed ID 8576152
Journal J Biol Chem
Year 1996
Volume 271
Pages 1551-7
Authors Ryle MJ, Lanzilotta WN, Seefeldt LC, Scarrow RC, Jensen GM
Title Circular dichroism and x-ray spectroscopies of Azotobacter vinelandii nitrogenase iron protein. MgATP and MgADP induced protein conformational changes affecting the [4Fe-4S] cluster and characterization of a [2Fe-2S] form.
Related PDB
Related UniProtKB
[45]
Resource
Comments
Medline ID
PubMed ID 9307010
Journal Biochem J
Year 1997
Volume 326
Pages 637-40
Authors Yousafzai FK, Eady RR
Title Nitrogenase of Klebsiella pneumoniae: kinetics of formation of the transition-state complex and evidence for an altered conformation of MoFe protein lacking a FeMoco centre.
Related PDB
Related UniProtKB
[46]
Resource
Comments
Medline ID
PubMed ID 9335558
Journal Biochemistry
Year 1997
Volume 36
Pages 12976-83
Authors Lanzilotta WN, Seefeldt LC
Title Changes in the midpoint potentials of the nitrogenase metal centers as a result of iron protein-molybdenum-iron protein complex formation.
Related PDB
Related UniProtKB
[47]
Resource
Comments X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS)
Medline ID 97178802
PubMed ID 9063865
Journal Biochemistry
Year 1997
Volume 36
Pages 1181-7
Authors Peters JW, Stowell MH, Soltis SM, Finnegan MG, Johnson MK, Rees DC
Title Redox-dependent structural changes in the nitrogenase P-cluster.
Related PDB 1min 2min 3min
Related UniProtKB P07328 P07329
[48]
Resource
Comments
Medline ID
PubMed ID 9271856
Journal FEMS Microbiol Lett
Year 1997
Volume 153
Pages 303-9
Authors Zehr JP, Harris D, Dominic B, Salerno J
Title Structural analysis of the Trichodesmium nitrogenase iron protein: implications for aerobic nitrogen fixation activity.
Related PDB
Related UniProtKB
[49]
Resource
Comments
Medline ID
PubMed ID 9102457
Journal J Mol Biol
Year 1997
Volume 266
Pages 642-8
Authors Grossman JG, Hasnain SS, Yousafzai FK, Smith BE, Eady RR
Title The first glimpse of a complex of nitrogenase component proteins by solution X-ray scattering: conformation of the electron transfer transition state complex of Klebsiella pneumoniae nitrogenase.
Related PDB
Related UniProtKB
[50]
Resource
Comments X-RAY CRYSTALLOGRAPHY (3.0 ANGSTROMS)
Medline ID 97305952
PubMed ID 9163420
Journal Nature
Year 1997
Volume 387
Pages 370-6
Authors Schindelin H, Kisker C, Schlessman JL, Howard JB, Rees DC
Title Structure of ADP x AIF4(-)-stabilized nitrogenase complex and its implications for signal transduction.
Related PDB 1n2c
Related UniProtKB P07328 P07329
[51]
Resource
Comments
Medline ID
PubMed ID 9730834
Journal Biochemistry
Year 1998
Volume 37
Pages 12611-23
Authors Christiansen J, Goodwin PJ, Lanzilotta WN, Seefeldt LC, Dean DR
Title Catalytic and biophysical properties of a nitrogenase Apo-MoFe protein produced by a nifB-deletion mutant of Azotobacter vinelandii.
Related PDB
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[52]
Resource
Comments
Medline ID
PubMed ID 9698385
Journal Biochemistry
Year 1998
Volume 37
Pages 11376-84
Authors Lanzilotta WN, Christiansen J, Dean DR, Seefeldt LC
Title Evidence for coupled electron and proton transfer in the [8Fe-7S] cluster of nitrogenase.
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[53]
Resource
Comments
Medline ID
PubMed ID 9425061
Journal Biochemistry
Year 1998
Volume 37
Pages 399-407
Authors Lanzilotta WN, Parker VD, Seefeldt LC
Title Electron transfer in nitrogenase analyzed by Marcus theory: evidence for gating by MgATP.
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[54]
Resource
Comments
Medline ID
PubMed ID 9710250
Journal FEBS Lett
Year 1998
Volume 432
Pages 55-8
Authors Spee JH, Arendsen AF, Wassink H, Marritt SJ, Hagen WR, Haaker H
Title Redox properties and electron paramagnetic resonance spectroscopy of the transition state complex of Azotobacter vinelandii nitrogenase.
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[55]
Resource
Comments
Medline ID
PubMed ID 9756863
Journal J Biol Chem
Year 1998
Volume 273
Pages 26330-7
Authors Angove HC, Yoo SJ, Munck E, Burgess BK
Title An all-ferrous state of the Fe protein of nitrogenase. Interaction with nucleotides and electron transfer to the MoFe protein.
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[56]
Resource
Comments
Medline ID
PubMed ID 9792679
Journal J Biol Chem
Year 1998
Volume 273
Pages 29678-85
Authors Bursey EH, Burgess BK
Title The role of methionine 156 in cross-subunit nucleotide interactions in the iron protein of nitrogenase.
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[57]
Resource
Comments
Medline ID
PubMed ID 9642255
Journal J Biol Chem
Year 1998
Volume 273
Pages 16927-34
Authors Bursey EH, Burgess BK
Title Characterization of a variant iron protein of nitrogenase that is impaired in its ability to adopt the MgATP-induced conformational change.
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[58]
Resource
Comments
Medline ID
PubMed ID 9677296
Journal J Mol Biol
Year 1998
Volume 280
Pages 669-85
Authors Schlessman JL, Woo D, Joshua-Tor L, Howard JB, Rees DC
Title Conformational variability in structures of the nitrogenase iron proteins from Azotobacter vinelandii and Clostridium pasteurianum.
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[59]
Resource
Comments
Medline ID
PubMed ID 9860849
Journal Biochemistry
Year 1998
Volume 37
Pages 17345-54
Authors Duyvis MG, Wassink H, Haaker H
Title Nitrogenase of Azotobacter vinelandii: kinetic analysis of the Fe protein redox cycle.
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[60]
Resource
Comments
Medline ID
PubMed ID 10215587
Journal Biochem J
Year 1999
Volume 339
Pages 511-5
Authors Yousafzai FK, Eady RR
Title MgATP-independent hydrogen evolution catalysed by nitrogenase: an explanation for the missing electron(s) in the MgADP-AlF4 transition-state complex.
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[61]
Resource
Comments
Medline ID
PubMed ID 10231529
Journal Biochemistry
Year 1999
Volume 38
Pages 5779-85
Authors Chan JM, Christiansen J, Dean DR, Seefeldt LC
Title Spectroscopic evidence for changes in the redox state of the nitrogenase P-cluster during turnover.
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[62]
Resource
Comments
Medline ID
PubMed ID 10364195
Journal J Biol Chem
Year 1999
Volume 274
Pages 17593-8
Authors Chan JM, Ryle MJ, Seefeldt LC
Title Evidence that MgATP accelerates primary electron transfer in a Clostridium pasteurianum Fe protein-Azotobacter vinelandii MoFe protein nitrogenase tight complex.
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[63]
Resource
Comments
Medline ID
PubMed ID 10391920
Journal J Biol Chem
Year 1999
Volume 274
Pages 19778-84
Authors Rangaraj P, Ryle MJ, Lanzilotta WN, Ludden PW, Shah VK
Title In vitro biosynthesis of iron-molybdenum cofactor and maturation of the nif-encoded apodinitrogenase. Effect of substitution for NifH with site-specifically altered forms of NifH.
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[64]
Resource
Comments X-ray crystallography
Medline ID
PubMed ID 10525412
Journal J Mol Biol
Year 1999
Volume 292
Pages 871-91
Authors Mayer SM, Lawson DM, Gormal CA, Roe SM, Smith BE
Title New insights into structure-function relationships in nitrogenase: A 1.6 A resolution X-ray crystallographic study of Klebsiella pneumoniae MoFe-protein.
Related PDB 1qgu 1qh1 1qh8
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[65]
Resource
Comments
Medline ID
PubMed ID 10852721
Journal Biochemistry
Year 2000
Volume 39
Pages 7221-8
Authors Chan JM, Wu W, Dean DR, Seefeldt LC
Title Construction and characterization of a heterodimeric iron protein: defining roles for adenosine triphosphate in nitrogenase catalysis.
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[66]
Resource
Comments
Medline ID
PubMed ID 10985789
Journal Biochemistry
Year 2000
Volume 39
Pages 11434-40
Authors Clarke TA, Maritano S, Eady RR
Title Formation of a tight 1:1 complex of Clostridium pasteurianum Fe protein-Azotobacter vinelandii MoFe protein: evidence for long-range interactions between the Fe protein binding sites during catalytic hydrogen evolution.
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[67]
Resource
Comments
Medline ID
PubMed ID 11087939
Journal Biochim Biophys Acta
Year 2000
Volume 1543
Pages 36-46
Authors Johnson JL, Nyborg AC, Wilson PE, Tolley AM, Nordmeyer FR, Watt GD
Title Mechanistic interpretation of the dilution effect for Azotobacter vinelandii and Clostridium pasteurianum nitrogenase catalysis.
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[68]
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Comments X-RAY CRYSTALLOGRAPHY (2.15 ANGSTROMS).
Medline ID 20552920
PubMed ID 11101289
Journal Biochemistry
Year 2000
Volume 39
Pages 14745-52
Authors Jang SB, Seefeldt LC, Peters JW
Title Insights into nucleotide signal transduction in nitrogenase: structure of an iron protein with MgADP bound.
Related PDB 1fp6
Related UniProtKB P00459
[69]
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Comments
Medline ID
PubMed ID 10651628
Journal Biochemistry
Year 2000
Volume 39
Pages 641-8
Authors Jang SB, Seefeldt LC, Peters JW
Title Modulating the midpoint potential of the [4Fe-4S] cluster of the nitrogenase Fe protein.
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[70]
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Comments
Medline ID
PubMed ID 11087938
Journal Biochim Biophys Acta
Year 2000
Volume 1543
Pages 24-35
Authors Johnson JL, Nyborg AC, Wilson PE, Tolley AM, Nordmeyer FR, Watt GD
Title Analysis of steady state Fe and MoFe protein interactions during nitrogenase catalysis.
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[71]
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Comments
Medline ID
PubMed ID 11006545
Journal Curr Opin Chem Biol
Year 2000
Volume 4
Pages 559-66
Authors Rees DC, Howard JB
Title Nitrogenase: standing at the crossroads.
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[72]
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Comments
Medline ID
PubMed ID 10837496
Journal J Biol Chem
Year 2000
Volume 275
Pages 17631-8
Authors Ribbe MW, Bursey EH, Burgess BK
Title Identification of an Fe protein residue (Glu146) of Azotobacter vinelandii nitrogenase that is specifically involved in FeMo cofactor insertion.
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[73]
Resource
Comments
Medline ID
PubMed ID 11311117
Journal Biochem J
Year 2001
Volume 355
Pages 569-76
Authors Durrant MC
Title Controlled protonation of iron-molybdenum cofactor by nitrogenase: a structural and theoretical analysis.
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[74]
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Comments
Medline ID
PubMed ID 11705370
Journal Biochemistry
Year 2001
Volume 40
Pages 13816-25
Authors Benton PM, Mayer SM, Shao J, Hoffman BM, Dean DR, Seefeldt LC
Title Interaction of acetylene and cyanide with the resting state of nitrogenase alpha-96-substituted MoFe proteins.
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[75]
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Comments X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS)
Medline ID 21093028
PubMed ID 11170380
Journal Biochemistry
Year 2001
Volume 40
Pages 641-50
Authors Chiu H, Peters JW, Lanzilotta WN, Ryle MJ, Seefeldt LC, Howard JB, Rees DC
Title MgATP-Bound and nucleotide-free structures of a nitrogenase protein complex between the Leu 127 Delta-Fe-protein and the MoFe-protein.
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[76]
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Comments
Medline ID
PubMed ID 11258953
Journal Biochemistry
Year 2001
Volume 40
Pages 3333-9
Authors Fisher K, Newton WE, Lowe DJ
Title Electron paramagnetic resonance analysis of different Azotobacter vinelandii nitrogenase MoFe-protein conformations generated during enzyme turnover: evidence for S = 3/2 spin states from reduced MoFe-protein intermediates.
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[77]
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Comments X-ray crystallography
Medline ID
PubMed ID 11327812
Journal Biochemistry
Year 2001
Volume 40
Pages 1540-9
Authors Sorlie M, Christiansen J, Lemon BJ, Peters JW, Dean DR, Hales BJ
Title Mechanistic features and structure of the nitrogenase alpha-Gln195 MoFe protein.
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[78]
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Comments
Medline ID
PubMed ID 11734043
Journal J Am Chem Soc
Year 2001
Volume 123
Pages 12392-410
Authors Lovell T, Li J, Liu T, Case DA, Noodleman L
Title FeMo cofactor of nitrogenase: a density functional study of states M(N), M(OX), M(R), and M(I).
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[79]
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Comments X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS).
Medline ID 21093029
PubMed ID 11170381
Journal Biochemistry
Year 2001
Volume 40
Pages 651-6
Authors Strop P, Takahara PM, Chiu H, Angove HC, Burgess BK, Rees DC
Title Crystal structure of the all-ferrous [4Fe-4S]0 form of the nitrogenase iron protein from Azotobacter vinelandii.
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[80]
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Comments
Medline ID
PubMed ID 12045096
Journal Annu Rev Biochem
Year 2002
Volume 71
Pages 221-46
Authors Rees DC
Title Great metalloclusters in enzymology.
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[81]
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Comments X-ray crystallography
Medline ID
PubMed ID 12501184
Journal Biochemistry
Year 2002
Volume 41
Pages 15557-65
Authors Schmid B, Einsle O, Chiu HJ, Willing A, Yoshida M, Howard JB, Rees DC
Title Biochemical and structural characterization of the cross-linked complex of nitrogenase: comparison to the ADP-AlF4(-)-stabilized structure.
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[82]
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Medline ID
PubMed ID 12401079
Journal Inorg Chem
Year 2002
Volume 41
Pages 5744-53
Authors Lovell T, Torres RA, Han WG, Liu T, Case DA, Noodleman L
Title Metal substitution in the active site of nitrogenase MFe(7)S(9) (M = Mo(4+), V(3+), Fe(3+)).
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[83]
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Comments
Medline ID
PubMed ID 11782173
Journal J Am Chem Soc
Year 2002
Volume 124
Pages 216-24
Authors Coucouvanis D, Han J, Moon N
Title Synthesis and characterization of sulfur-voided cubanes. Structural analogues for the MoFe(3)S(3) subunit in the nitrogenase cofactor.
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[84]
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Comments X-ray crystallography
Medline ID
PubMed ID 12133839
Journal J Biol Chem
Year 2002
Volume 277
Pages 35263-6
Authors Mayer SM, Gormal CA, Smith BE, Lawson DM
Title Crystallographic analysis of the MoFe protein of nitrogenase from a nifV mutant of Klebsiella pneumoniae identifies citrate as a ligand to the molybdenum of iron molybdenum cofactor (FeMoco).
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[85]
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Comments
Medline ID
PubMed ID 12176981
Journal J Biol Chem
Year 2002
Volume 277
Pages 40106-11
Authors Rangaraj P, Ludden PW
Title Accumulation of 99Mo-containing iron-molybdenum cofactor precursors of nitrogenase on NifNE, NifH, and NifX of Azotobacter vinelandii.
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[86]
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Medline ID
PubMed ID 11913144
Journal Met Ions Biol Syst
Year 2002
Volume 39
Pages 75-119
Authors Lawson DM, Smith BE
Title Molybdenum nitrogenases: a crystallographic and mechanistic view.
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[87]
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Comments X-RAY CRYSTALLOGRAPHY (1.16 ANGSTROMS)
Medline ID 22204524
PubMed ID 12215645
Journal Science
Year 2002
Volume 297
Pages 1696-700
Authors Einsle O, Tezcan FA, Andrade SL, Schmid B, Yoshida M, Howard JB, Rees DC
Title Nitrogenase MoFe-protein at 1.16 A resolution: a central ligand in the FeMo-cofactor.
Related PDB 1m1n
Related UniProtKB P07328 P07329
[88]
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Comments X-RAY CRYSTALLOGRAPHY (2.3 ANGSTROMS)
Medline ID 21948294
PubMed ID 11951047
Journal Science
Year 2002
Volume 296
Pages 352-6
Authors Schmid B, Ribbe MW, Einsle O, Yoshida M, Thomas LM, Dean DR, Rees DC, Burgess BK
Title Structure of a cofactor-deficient nitrogenase MoFe protein.
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[89]
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Comments
Medline ID
PubMed ID 12506366
Journal Chemistry
Year 2003
Volume 9
Pages 76-87
Authors Pickett CJ, Vincent KA, Ibrahim SK, Gormal CA, Smith BE, Best SP
Title Electron-transfer chemistry of the iron-molybdenum cofactor of nitrogenase: delocalized and localized reduced states of FeMoco which allow binding of carbon monoxide to iron and molybdenum.
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[90]
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Comments
Medline ID
PubMed ID 15102840
Journal J Biol Chem
Year 2004
Volume 279
Pages 28276-82
Authors Corbett MC, Hu Y, Naderi F, Ribbe MW, Hedman B, Hodgson KO
Title Comparison of iron-molybdenum cofactor-deficient nitrogenase MoFe proteins by X-ray absorption spectroscopy: implications for P-cluster biosynthesis.
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[91]
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Comments
Medline ID
PubMed ID 15549494
Journal J Biol Inorg Chem
Year 2004
Volume 9
Pages 1028-33
Authors Jang SB, Jeong MS, Seefeldt LC, Peters JW
Title Structural and biochemical implications of single amino acid substitutions in the nucleotide-dependent switch regions of the nitrogenase Fe protein from Azotobacter vinelandii.
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[92]
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Comments
Medline ID
PubMed ID 14967020
Journal Biochemistry
Year 2004
Volume 43
Pages 1787-97
Authors Sen S, Igarashi R, Smith A, Johnson MK, Seefeldt LC, Peters JW
Title A conformational mimic of the MgATP-bound "on state" of the nitrogenase iron protein.
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[93]
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Comments
Medline ID
PubMed ID 15650336
Journal Mol Cells
Year 2004
Volume 18
Pages 374-82
Authors Jeong MS, Jang SB
Title Structural basis for the changes in redox potential in the nitrogenase Phe135Trp Fe protein with MgADP Bound.
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[94]
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Comments
Medline ID
PubMed ID 16123301
Journal Science
Year 2005
Volume 309
Pages 1377-80
Authors Tezcan FA, Kaiser JT, Mustafi D, Walton MY, Howard JB, Rees DC
Title Nitrogenase complexes: multiple docking sites for a nucleotide switch protein.
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[95]
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Medline ID
PubMed ID 16616373
Journal J Inorg Biochem
Year 2006
Volume 100
Pages 1041-52
Authors Sen S, Krishnakumar A, McClead J, Johnson MK, Seefeldt LC, Szilagyi RK, Peters JW
Title Insights into the role of nucleotide-dependent conformational change in nitrogenase catalysis: Structural characterization of the nitrogenase Fe protein Leu127 deletion variant with bound MgATP.
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Comments
This enzyme is homologous to that from Klebsiella pneumoniae and Azotobacter vinelandii (M00114 in EzCatDB).
This enzyme, Nitrogenase, is composed of molybdenum-iron protein component (MoFe protein; component 1) and iron protein (Fe protein; component 2). The Fe protein component (component 2) transfer electrons to another enzyme component, MoFe protein (component 1).
The Fe protein component is a homodimer, which binds two MgATP molecules and one [4Fe-4S] cluster on the interface of the dimer.
The MoFe protein is a heterotetramer, composed of two alpha subunits and two beta subunits. The alpha subunit binds a cofactor called, FeMoco centre, which is composed of molybdenum, [7Fe-9S], and homocitrate, whereas the interface of the alpha and beta subunits binds a cofactor, called P cluster, that is [8Fe-7S].
This enzyme catalyzes the following reactions:
(A) Electron transfer from FMN of flavodoxin or [2Fe-2S] of ferredoxin to the [4Fe-4S] cluster of Fe protein:
(X) Binding of MgATP molecules to the Fe proteins induces the conformational change, leading to the reaction (B):
(B) Electron transfer from the [4Fe-4S] cluster to the P-cluster([8Fe-7S]):
(C) Hydrolysis of two ATP molecules to produce two ADP molecules, leading to the conformational change in disconnection between the Fe protein and MoFe protein, which inhibits the reaction (B) (Fe protein):
(D) Electron transfer from the P-cluster([8Fe-7S]) to the FeMoco centre:
(E) Hydrogenation (H2 production from 2 H+ ions) at the FeMoco centre:
(F) Nitorogenation (NH3 production from N2 and H+ ions) at the FeMoco centre:
###
This enzyme catalyzes N2 reduction:
N2 + 8 H+ + 8 e- => 2 NH3 + H2
(1) 2 H+ + 2 e- => H2
(2) N2 + 6 H+ + 6 e- => 2 NH3
Thus, the reactions (E) and (F) (or the MoFe protein cycle) consists of eight sequential one-electron steps [reactions, (A)-(D)], each of which corresponds to an Fe protein cycle (see [12], [86]).
###
(A) Electron transfer from FMN of flavodoxin or [2Fe-2S] of ferredoxin to the [4Fe-4S] cluster of Fe protein(see [93], [94]):
(B) Electron transfer from the [4Fe-4S] cluster to the P-cluster([8Fe-7S]):
(B1) Indirect transfer from the [4Fe-4S] cluster to the P-cluster through Cys94 (bound to [4Fe-4S]), Thr110 and Cys106 (bound to P-cluster).
(C) Hydrolysis of two ATP molecules to produce two ADP molecules on the Fe protein (see [16], [17], [18], [35], [91]):
(C1) The negative charge of gamma-phsohate group is stabilized by the magnesium ion bound to Ser15, and Lysine residues (Lys9, Lys14, Lys40), and mainchain amide group of Gly11.
(C2) Either Asp38 or Asp126 from the adjacent subunit acts as a general base to deprotonate and activate the water molecule. However, this water is not bound to the magnesium ion.
(C3) The activated water molecule makes a nucleophilic attack on the phosphorus atom of the gamma-phosphate.
(C4) The transition-state must be stabilized by the above stabilizer residues and cofactor.
(C5) The reaction completes.
(D) Electron transfer from the P-cluster([8Fe-7S]) to the FeMoco centre (see [20], [33], [74]):
(D1) Indirect transfer from the the P-cluster to the FeMoco centre through Cys53 (bound to P-cluster), Gln182 (bound to homocitrate), and homocitrate itself (bound to FeMoco).
(E) Hydrogenation (H2 production from 2 H+ ions) at the FeMoco centre (see [20], [73]):
(F) Nitorogenation (NH3 production from N2 and H+ ions) at the FeMoco centre (see [24], [87], [89]):

Created Updated
2005-04-25 2009-02-26