I3R9M9 · NARG_HALMT
- ProteinRespiratory nitrate reductase subunit alpha
- GenenarG
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids984 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
The respiratory membrane-bound nitrate reductase enzyme complex plays a role in generation of metabolic energy by using nitrate as a terminal electron acceptor during anaerobic conditions. The alpha chain is the actual site of nitrate reduction.
Catalytic activity
- a quinol + nitrate = a quinone + H2O + nitrite
Cofactor
Protein has several cofactor binding sites:
Note: Binds 1 [4Fe-4S] cluster per subunit.
Note: Binds 1 molybdenum-bis(molybdopterin guanine dinucleotide) (Mo-bis-MGD) cofactor per subunit.
Activity regulation
Inhibited by cyanide, azide and antimycin A. Enzyme stability is not dependent on salt concentration.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
0.82 mM | nitrate | |||||
0.25 mM | methyl viologen |
Characterized with purified enzyme corresponding to a dimer of NarG and NarH.
pH Dependence
Optimum pH is 8.2. At 40 degrees Celsius (temperature of natural environment) the optimum pH is 7.9.
Temperature Dependence
Optimum temperature is 70 degrees Celsius.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 110 | [4Fe-4S] cluster (UniProtKB | ChEBI) | ||||
Sequence: H | ||||||
Binding site | 114 | [4Fe-4S] cluster (UniProtKB | ChEBI) | ||||
Sequence: C | ||||||
Binding site | 118 | [4Fe-4S] cluster (UniProtKB | ChEBI) | ||||
Sequence: C | ||||||
Binding site | 153 | [4Fe-4S] cluster (UniProtKB | ChEBI) | ||||
Sequence: C | ||||||
Binding site | 249 | Mo (UniProtKB | ChEBI) of Mo-bis(molybdopterin guanine dinucleotide) (UniProtKB | ChEBI) | ||||
Sequence: D |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | plasma membrane | |
Molecular Function | 4 iron, 4 sulfur cluster binding | |
Molecular Function | metal ion binding | |
Molecular Function | molybdopterin cofactor binding | |
Molecular Function | nitrate reductase (quinone) activity | |
Biological Process | anaerobic respiration | |
Biological Process | nitrate assimilation |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameRespiratory nitrate reductase subunit alpha
- EC number
- Alternative names
Gene names
Encoded on
- Plasmid pHM300
Organism names
- Strain
- Taxonomic lineageArchaea > Euryarchaeota > Stenosarchaea group > Halobacteria > Halobacteriales > Haloferacaceae > Haloferax
Accessions
- Primary accessionI3R9M9
- Secondary accessions
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Cell membrane ; Peripheral membrane protein
Keywords
- Cellular component
PTM/Processing
Features
Showing features for chain, signal.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000428886 | ?-984 | Respiratory nitrate reductase subunit alpha | |||
Sequence: MSRNDASQLDDGETTAESPPDDQANDAPEVGDPPGDPVDADSGVSRRTFLEGIGVASLLGIGTSAASDDSLFQMGGLKPVDDPIGNYPYRDWEDLYREKWDWDSVSRSTHSVNCTGSCSWNVYVKNGQVWREEQSGDYPRFDESLPDPNPRGCQKGACYTDYVNADQRIKHPLKRVGERGEGKWKRISWDEALTEIAEHVVDEVEAGRYDAISGFTPIPAMSPVSFASGSRLVNLLGGVSHSFYDWYSDLPPGQPITWGTQTDNAESADWYNADYIIAWGSNINVTRIPDAKYFLESGYNGTKRVGVFTDYSQTAIHTDEWLSPDSGTDTALALGMAQTIVDEGLYDEAHLKEQTDMPLLVRQDTGKFLRASDVPSVNTDADRPEWMLLMLDSNGRIREAPGSLGERDGQKDYSKSIELDFDPQLDGETTVQTQSGRVQVRTVWAELRDELANWDPEMVHEETTVGKETYQRIAREFAEADKAKIIQGKGVNDWYHNDLGNRALQLLVTLTGNLGEQGTGLDHYVGQEKIWTFHGWKTLSFPTGKVRGVPTTLWTYYHAGILDNTDPDTAAKIRESIDKGWMPVYPEERDNGSRPDPTTMFVWRGNYFNQAKGNVAVEEQLWPKLDLVVDINFRMDSTAMYSDIVLPTASHYEKHDLSMTDMHTYVHPFTPAVEPLGESKTDWQIFRELAQKIQEVATERGVEPISDRKFDREIDLQSVYDDYVRDWETGEEGALAEDRAACEYILEHSEESNPADSDEQITFADTVEQPQRLLEAGDHWTSDIEDGEAYAPWKDFVQDKNPWPTVTGRQQYYIDHDWFLELGEELPTHKEGPENTGGDYPMEYNTPHGRWAIHSTWRDSEKLLRLQRGEPLLYLHPEDAEERGIEDGDSVEVFNDLAEVELQAKIYPSSQRGTARMYFAWERFQFDSDSNFNSLVPMYMKPTQLVQYPEDSGEHLHFFPNYWGPTGVNSDVRVDVRKAGGGDE | ||||||
Signal | 1-? | Tat-type signal |
Post-translational modification
Exported by the Tat system.
Expression
Induction
By nitrate.
Interaction
Subunit
Probable multiprotein complex; a catalytic heterodimer of an alpha and beta chain is proposed to associate with additional subunits involved in membrane attachment and electron transfer.
Structure
Family & Domains
Features
Showing features for region, compositional bias, domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 1-43 | Disordered | ||||
Sequence: MSRNDASQLDDGETTAESPPDDQANDAPEVGDPPGDPVDADSG | ||||||
Compositional bias | 7-21 | Polar residues | ||||
Sequence: SQLDDGETTAESPPD | ||||||
Domain | 103-167 | 4Fe-4S Mo/W bis-MGD-type | ||||
Sequence: DSVSRSTHSVNCTGSCSWNVYVKNGQVWREEQSGDYPRFDESLPDPNPRGCQKGACYTDYVNADQ |
Sequence similarities
Belongs to the prokaryotic molybdopterin-containing oxidoreductase family.
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Sequence processingThe displayed sequence is further processed into a mature form.
- Length984
- Mass (Da)111,326
- Last updated2012-09-05 v1
- Checksum4CECDC63C15F628E
Features
Showing features for compositional bias, sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Compositional bias | 7-21 | Polar residues | ||||
Sequence: SQLDDGETTAESPPD | ||||||
Sequence conflict | 281-282 | in Ref. 1; CAF21906 | ||||
Sequence: SN → VE | ||||||
Sequence conflict | 429-434 | in Ref. 1; CAF21906 | ||||
Sequence: TTVQTQ → QRSNP | ||||||
Sequence conflict | 564-566 | in Ref. 1; CAF21906 | ||||
Sequence: NTD → TPN | ||||||
Sequence conflict | 603 | in Ref. 1; CAF21906 | ||||
Sequence: W → R | ||||||
Sequence conflict | 694 | in Ref. 1; CAF21906 | ||||
Sequence: Q → L | ||||||
Sequence conflict | 709 | in Ref. 1; CAF21906 | ||||
Sequence: K → R | ||||||
Sequence conflict | 833 | in Ref. 1; CAF21906 | ||||
Sequence: P → S |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AJ621880 EMBL· GenBank· DDBJ | CAF21906.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
CP001870 EMBL· GenBank· DDBJ | AFK20939.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AOLO01000001 EMBL· GenBank· DDBJ | EMA05271.1 EMBL· GenBank· DDBJ | Genomic DNA |