glbN Resolved · high auto-curated
H37Rv Rv1542c · MTBC0 mtbc0_001649 ·
136 aa · 1754235–1754645 (-) ·
RefSeq NP_216058.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | hemoglobin GlbN |
|---|---|
| MTBC0 PGAP re-annotation | group 1 truncated hemoglobin GlbN |
| Revised (this work) | Group 1 truncated hemoglobin GlbN. Pfam: Bac_globin (PF01152.28). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WN25
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Group 1 truncated hemoglobin GlbN |
| Curated function | Binds oxygen cooperatively with very high affinity (P(50) = 0.013 mmHg at 20 degrees Celsius) because of a fast combination (25 microM(-1)sec(-1)) and a slow dissociation (0.2 sec(-1)) rate. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
C Energy production and conversion
|
|---|---|
| Preferred name | glbN |
| eggNOG description | Group 1 truncated hemoglobin |
| Orthologous group | COG2346 |
| KEGG orthology |
K06886
|
| Gene Ontology (76) |
GO:0001505, GO:0003674, GO:0003824, GO:0005488, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0006807, GO:0008144, GO:0008150 +64 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 | n/a |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 0 synonymous, 1 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 |
|---|---|---|---|---|
Bac_globin | PF01152.28 | 2.3e-36 | 14–127 | Bacterial-like globin |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: lprI (lipoprotein LprI), medium confidence from genomic context alone (score 661 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv1541c lprI |
lipoprotein LprI | 697 | 661 ctx | neighborhood:656 |
Rv1544 |
ketoacyl reductase | 540 | 540 ctx | neighborhood:540 |
Rv1543 |
oxidoreductase | 699 | 493 ctx | neighborhood:490 textmining:430 |
Rv1545 hyp |
hypothetical protein | 455 | 455 ctx | neighborhood:455 |
Rv2466c hyp |
hypothetical protein | 500 | 449 | coexpression:417 |
Rv1546 hyp |
hypothetical protein | 435 | 435 ctx | neighborhood:435 |
Rv1547 dnaE1 |
DNA polymerase III subunit alpha | 433 | 433 ctx | neighborhood:432 |
Rv0385 |
monooxygenase | 884 | 373 | textmining:824 |
Rv0267 narU |
nitrite extrusion protein NarU | 533 | 180 | textmining:454 |
Rv0261c narK3 |
nitrate/nitrite transporter | 666 | 105 | textmining:643 |
Rv1705c PPE22 |
PPE family protein PPE22 | 524 | 67 | textmining:511 |
Rv1360 |
oxidoreductase | 663 | 63 | textmining:656 |
Rv3125c PPE49 |
PPE family protein PPE49 | 518 | 55 | textmining:511 |
Rv1548c PPE21 |
PPE family protein PPE21 | 654 | 50 | textmining:651 |
Rv1528c papA4 |
polyketide synthase associated protein PapA | 436 | 50 | textmining:431 |
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: hemoglobin GlbN
- MTBC0 PGAP product: group 1 truncated hemoglobin GlbN
- Pfam (hmmscan --cut_ga): Bac_globin PF01152.28 (E=2e-36)
- (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_216058.1)
- Domains: Pfam-A via hmmscan --cut_ga — Bac_globin (PF01152.28)
- 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
COG2346 - Curated reference: UniProt P9WN25 (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 —
20 functional partner(s); context anchor
lprI - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_001649|Rv1542c|glbN MGLLSRLRKREPISIYDKIGGHEAIEVVVEDFYVRVLADDQLSAFFSGTNMSRLKGKQVEFFAAALGGPEPYTGAPMKQVHQGRGITMHHFSLVAGHLADALTAAGVPSETITEILGVIAPLAVDVTSGESTTAPV