narG Family assigned · medium auto-curated
H37Rv Rv1161 · MTBC0 mtbc0_001250 ·
1232 aa · 1295769–1299467 (+) ·
RefSeq NP_215677.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | nitrate reductase subunit alpha |
|---|---|
| MTBC0 PGAP re-annotation | nitrate reductase subunit alpha |
| Revised (this work) | Nitrate reductase subunit alpha. Pfam: Molybdopterin (PF00384.28), NarG_dom_V (PF28599.1), Molydop_binding (PF01568.28). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WJQ3
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Nitrate reductase alpha subunit |
| EC (curated) |
EC 1.7.5.1
|
| Curated function | The alpha chain is the actual site of nitrate reduction (Probable). Supports anaerobic growth of E.coli on glycerol in an E.coli mutant lacking endogenous nitrate reductase. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
C Energy production and conversion
|
|---|---|
| Preferred name | narG |
| eggNOG description | Belongs to the prokaryotic molybdopterin-containing oxidoreductase family |
| Orthologous group | COG5013 |
| EC number |
EC 1.7.5.1
|
| KEGG orthology |
K00370
|
| KEGG pathways |
map00910, map01120, map02020
|
| KEGG modules |
M00529, M00530, M00804
|
| Gene Ontology (64) |
GO:0000302, GO:0001101, GO:0003674, GO:0003824, GO:0005575, GO:0005576, GO:0005618, GO:0005623, GO:0005886, GO:0006082, GO:0006807, GO:0006950 +52 more
|
Orthology-based transfer (eggNOG 5.0.2, diamond). EC/KO/GO/CAZy are computed annotations, not manual curation; cross-check against the primary literature before treating a specific reaction as established.
Conservation & selection (intra-MTBC, 145 209 strains)
| pN/pS | 0.301 · purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 14 synonymous, 13 missense, 0 nonsense, 0 frameshift |
pN/pS from segregating SNPs (singletons removed) normalised by possible sites. Low pN/pS = purifying selection (a strong signal that a "hypothetical" is a real, constrained gene). A high pN/pS is ambiguous: relaxed constraint or positive selection (drug resistance, antigenic variation) inflate it; e.g. rpoB/katG/pncA score high here for resistance, not loss of function. A clonal disruption (one allele over a clade) suggests lineage pseudogenisation; a convergent one (many independent alleles) is typical of resistance loss-of-function.
Domains (Pfam, hmmscan --cut_ga)
| Pfam | Accession | i-Evalue | Residues | Description |
|---|---|---|---|---|
Molybdopterin | PF00384.28 | 2.8e-60 | 118–828 | Molybdopterin oxidoreductase |
NarG_dom_V | PF28599.1 | 5.6e-48 | 908–1028 | Nitrate reductase alpha chain, domain V |
Molydop_binding | PF01568.28 | 4.0e-20 | 1086–1195 | Molydopterin dinucleotide binding domain |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: narH (nitrate reductase subunit beta), high confidence from genomic context alone (score 1000 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv1162 narH |
nitrate reductase subunit beta | 999 | 1000 ctx | neighborhood:825 cooccurence:774 coexpression:961 experimental:829 database:900 textmining:921 |
Rv1164 narI |
nitrate reductase subunit gamma | 999 | 1000 ctx | neighborhood:763 cooccurence:774 coexpression:797 experimental:773 database:900 textmining:939 |
Rv1163 narJ |
nitrate reductase subunit delta | 999 | 998 ctx | neighborhood:763 cooccurence:774 coexpression:932 experimental:510 textmining:937 |
Rv1737c narK2 |
nitrate/nitrite transporter | 998 | 988 ctx | cooccurence:759 coexpression:449 database:900 textmining:853 |
Rv0267 narU |
nitrite extrusion protein NarU | 994 | 985 ctx | cooccurence:719 coexpression:460 database:900 textmining:672 |
Rv2329c narK1 |
nitrate/nitrite transporter | 993 | 984 ctx | cooccurence:717 coexpression:446 database:900 textmining:627 |
Rv0261c narK3 |
nitrate/nitrite transporter | 990 | 984 ctx | cooccurence:702 coexpression:449 database:900 textmining:464 |
Rv0252 nirB |
nitrite reductase large subunit NirB | 970 | 948 | coexpression:484 database:900 textmining:465 |
Rv0253 nirD |
nitrite reductase small subunit NirD | 964 | 942 | coexpression:430 database:900 textmining:410 |
Rv1736c narX |
nitrate reductase-like protein NarX | 917 | 910 | database:900 |
Rv2781c |
oxidoreductase | 901 | 902 | database:900 |
Rv0021c hyp |
hypothetical protein | 900 | 901 | database:900 |
Rv2194 qcrC |
ubiquinol-cytochrome C reductase cytochrome subunit C | 854 | 801 | experimental:788 |
Rv1165 typA |
GTP-binding translation elongation factor | 786 | 761 ctx | neighborhood:746 |
Rv1166 lpqW |
monoacyl phosphatidylinositol tetramannoside-binding protein LpqW | 693 | 694 ctx | neighborhood:686 |
STRING combines evidence channels (neighborhood, fusion, cooccurrence, coexpression, experimental, database, text-mining) into a 0–1000 score. The ctx badge marks edges carried by the genomic-context channels (conserved neighborhood, fusion, phylogenetic co-occurrence), which are independent of orthology and structure and the strongest signal for an unknown gene. The no text-mining column recomputes the score from data alone, so a link that does not depend on the literature is visible. Association is a function hypothesis, not proof: corroborate with the operon context and the primary literature before assigning a function.
Evidence
- Legacy H37Rv annotation: nitrate reductase subunit alpha
- MTBC0 PGAP product: nitrate reductase subunit alpha
- Pfam (hmmscan --cut_ga): Molybdopterin PF00384.28 (E=3e-60), NarG_dom_V PF28599.1 (E=6e-48), Molydop_binding PF01568.28 (E=4e-20)
- (auto-curated by rules from PGAP + Pfam + Foldseek; not hand-reviewed)
Sources
- Ancestral sequence & coordinates: Harrison LB et al. (2024), An imputed ancestral reference genome for the MTBC, doi:10.1101/2023.09.07.556366
- Product annotation: NCBI PGAP on MTBC0; legacy from H37Rv NC_000962.3 (RefSeq NP_215677.1)
- Domains: Pfam-A via hmmscan --cut_ga — Molybdopterin (PF00384.28), NarG_dom_V (PF28599.1), Molydop_binding (PF01568.28)
- Sequence-level signal: ESM Atlas (EvolutionaryScale × BioHub) — exploratory
- Controlled vocabulary: eggNOG-mapper 2.1.12 (Cantalapiedra et al. 2021,
doi:10.1093/molbev/msab293), eggNOG 5.0 DB
(Huerta-Cepas et al. 2019) — OG
COG5013 - Curated reference: UniProt P9WJQ3 (SwissProt, reviewed; Evidence at protein level)
- Intra-MTBC selection: pN/pS and disruption from SPDI variants of 145 209 MTBC strains (this work, local collection vs H37Rv NC_000962.3)
- Interaction network: STRING v12.0 (Szklarczyk et al. 2023,
doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 —
48 functional partner(s); context anchor
narH - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_001250|Rv1161|narG MTVTPHVGGPLEELLERSGRFFTPGEFSADLRTVTRRGGREGDVFYRDRWSHDKVVRSTHGVNCTGSCSWKIYVKDGIITWETQQTDYPSVGPDRPEYEPRGCPRGASFSWYSYSPTRVRYPYARGVLVEMYREAKTRLGDPVLAWADIQADPERRRRYQQARGKGGLVRVSWAEASEMVAAAHVHTIKTYGPDRVAGFSPIPAMSMVSHAAGSRFVELIGGVMTSFYDWYADLPVASPQVFGDQTDVPESGDWWDASYLVMWGSNVPITRTPDAHWMAEARYRGAKVVVVSPDYADNTKFADEWVRCAAGTDTALAMAMGHVILSECYVRNQVPFFVDYVRRYTDLPFLIKLEKRGDLLVPGKFLTAADIGEESENAAFKPALLDELTNTVVVPQGSLGFRFGEDGVGKWNLDLGSVVPALSVEMDKAVNGDRSAELVTLPSFDTIDGHGETVSRGVPVRRAGKHLVCTVFDLMLAHYGVARAGLPGEWPTGYHDRTQQNTPAWQESITGVPAAQAIRFAKEFARNATESGGRSMIIMGGGICHWFHSDVMYRSVLALLMLTGSMGRNGGGWAHYVGQEKVRPLTGWQTMAMATDWSRPPRQVPGASYWYAHTDQWRYDGYGADKLASPVGRGRFAGKHTMDLLTSATAMGWSPFYPQFDRSSLDVADEARAAGRDVGDYVAEQLAQHKLKLSITDPDNPVNWPRVLTVWRANLIGSSGKGGEYFLRHLLGTDSNVQSDPPTDGVHPRDVVWDSDIPEGKLDLIMSIDFRMTSTTLVSDVVLPAATWYEKSDLSSTDMHPYVHSFSPAIDPPWETRSDFDAFAAIARAFSALAKRHLGTRTDVVLTALQHDTPDEMAYPDGTERDWLATGEVPVPGRTMSKLTVVERDYTAIYDKWLTLGPLIDQFGMTTKGYTVHPFREVSELAANFGVMNSGVAVGRPAITTAKRMADVILALSGTCNGRLAVEGFLELEKRTGQRLAHLAEGSEERRITYADTQARPVPVITSPEWSGSESGGRRYAPFTINIEHLKPFHTLTGRMHFYLAHDWVEELGEQLPVYRPPLDMARLFNQPELGPTDDGLGLTVRYLTPHSKWSFHSTYQDNLYMLSLSRGGPTMWMSPGDAAKINVRDNDWVEAVNANGIYVCRAIVSHRMPEGVVFVYHVQERTVDTPRTETNGKRGGNHNALTRVRIKPSHLAGGYGQHAFAFNYLGPTGNQRDEVTVVRRRSQEVRY