P07329 · NIFK_AZOVI
- ProteinNitrogenase molybdenum-iron protein beta chain
- GenenifK
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids523 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
This molybdenum-iron protein is part of the nitrogenase complex that catalyzes the key enzymatic reactions in nitrogen fixation.
Catalytic activity
- 16 ATP + 16 H2O + N2 + 8 reduced [2Fe-2S]-[ferredoxin] = 16 ADP + 6 H+ + H2 + 2 NH4+ + 8 oxidized [2Fe-2S]-[ferredoxin] + 16 phosphate
16 CHEBI:30616 + 16 CHEBI:15377 + CHEBI:17997 + 8 RHEA-COMP:10001 = 16 CHEBI:456216 + 6 CHEBI:15378 + CHEBI:18276 + 2 CHEBI:28938 + 8 RHEA-COMP:10000 + 16 CHEBI:43474
Cofactor
Note: Binds 1 [8Fe-7S] cluster per heterodimer.
Activity regulation
Nitrogenase holoenzyme is subject to 'conformational protection' by FeSII; under oxidizing conditions FeSII binds to the holoenzyme and reversibly protects it from oxidation (PubMed:7830548).
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 70 | [8Fe-7S] cluster (UniProtKB | ChEBI); ligand shared with alpha chain | ||||
Sequence: C | ||||||
Binding site | 95 | [8Fe-7S] cluster (UniProtKB | ChEBI); ligand shared with alpha chain | ||||
Sequence: C | ||||||
Binding site | 153 | [8Fe-7S] cluster (UniProtKB | ChEBI); ligand shared with alpha chain | ||||
Sequence: C | ||||||
Binding site | 188 | [8Fe-7S] cluster (UniProtKB | ChEBI); ligand shared with alpha chain | ||||
Sequence: S |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | molybdenum-iron nitrogenase complex | |
Molecular Function | ATP binding | |
Molecular Function | carbonyl sulfide nitrogenase activity | |
Molecular Function | iron-sulfur cluster binding | |
Molecular Function | metal ion binding | |
Molecular Function | nitrogenase activity | |
Biological Process | nitrogen fixation |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameNitrogenase molybdenum-iron protein beta chain
- EC number
- Alternative names
Gene names
Organism names
- Organism
- Strain
- Taxonomic lineageBacteria > Pseudomonadota > Gammaproteobacteria > Pseudomonadales > Pseudomonadaceae > Azotobacter
Accessions
- Primary accessionP07329
Subcellular Location
UniProt Annotation
GO Annotation
PTM/Processing
Features
Showing features for initiator methionine, chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Initiator methionine | 1 | Removed | ||||
Sequence: M | ||||||
Chain | PRO_0000153091 | 2-523 | Nitrogenase molybdenum-iron protein beta chain | |||
Sequence: SQQVDKIKASYPLFLDQDYKDMLAKKRDGFEEKYPQDKIDEVFQWTTTKEYQELNFQREALTVNPAKACQPLGAVLCALGFEKTMPYVHGSQGCVAYFRSYFNRHFREPVSCVSDSMTEDAAVFGGQQNMKDGLQNCKATYKPDMIAVSTTCMAEVIGDDLNAFINNSKKEGFIPDEFPVPFAHTPSFVGSHVTGWDNMFEGIARYFTLKSMDDKVVGSNKKINIVPGFETYLGNFRVIKRMLSEMGVGYSLLSDPEEVLDTPADGQFRMYAGGTTQEEMKDAPNALNTVLLQPWHLEKTKKFVEGTWKHEVPKLNIPMGLDWTDEFLMKVSEISGQPIPASLTKERGRLVDMMTDSHTWLHGKRFALWGDPDFVMGLVKFLLELGCEPVHILCHNGNKRWKKAVDAILAASPYGKNATVYIGKDLWHLRSLVFTDKPDFMIGNSYGKFIQRDTLHKGKEFEVPLIRIGFPIFDRHHLHRSTTLGYEGAMQILTTLVNSILERLDEETRGMQATDYNHDLVR |
Expression
Induction
Constitutively expressed during log and stationary phase in sucrose-limited cultures, its levels decrease during stationary phase (at protein level).
Interaction
Subunit
Tetramer of two alpha and two beta chains. Forms complex with the iron protein (nitrogenase component 2).
Structure
Sequence
- Sequence statusComplete
- Length523
- Mass (Da)59,460
- Last updated2007-01-23 v3
- ChecksumB6ECD633A24998F2
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 103 | in Ref. 2; AAA22144 | ||||
Sequence: F → L |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
M20568 EMBL· GenBank· DDBJ | AAA64711.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
M11579 EMBL· GenBank· DDBJ | AAA22144.1 EMBL· GenBank· DDBJ | Genomic DNA |