hemK Resolved · high auto-curated
H37Rv Rv1300 · MTBC0 mtbc0_001392 ·
325 aa · 1465604–1466581 (+) ·
RefSeq NP_215816.1
Annotation: from legacy to revised
| Legacy (H37Rv / Mycobrowser) | release factor glutamine methyltransferase |
|---|---|
| MTBC0 PGAP re-annotation | peptide chain release factor N(5)-glutamine methyltransferase |
| Revised (this work) | Peptide chain release factor N(5)-glutamine methyltransferase. Pfam: PrmC_N (PF17827.7), MTS (PF05175.21), Methyltransf_25 (PF13649.13), Methyltransf_31 (PF13847.13), Methyltransf_11 (PF08241.19). |
Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.
Curated reference (UniProt)
| UniProt |
P9WHV3
SwissProt · reviewed
· Evidence at protein level
|
|---|---|
| UniProt name | Release factor glutamine methyltransferase |
| EC (curated) |
EC 2.1.1.297
|
| Curated function | Methylates the class 1 translation termination release factors RF1/PrfA and RF2/PrfB on the glutamine residue of the universally conserved GGQ motif. |
Functional vocabulary (eggNOG-mapper, orthology transfer)
| COG category |
J Translation, ribosomal structure and biogenesis
|
|---|---|
| Preferred name | prmC |
| eggNOG description | Methylates the class 1 translation termination release factors RF1 PrfA and RF2 PrfB on the glutamine residue of the universally conserved GGQ motif |
| Orthologous group | COG2890 |
| EC number |
EC 2.1.1.297
|
| KEGG orthology |
K02493
|
| Gene Ontology (18) |
GO:0003674, GO:0003824, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0008150, GO:0008152, GO:0008168, GO:0008757, GO:0016740 +6 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 | 0.362 · purifying |
|---|---|
| Polymorphic sites (≥ 0.1% of strains) | 2 synonymous, 2 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 |
|---|---|---|---|---|
PrmC_N | PF17827.7 | 1.5e-12 | 26–94 | PrmC N-terminal domain |
MTS | PF05175.21 | 9.6e-06 | 133–216 | Methyltransferase small domain |
Methyltransf_25 | PF13649.13 | 5.8e-08 | 134–209 | Methyltransferase domain |
Methyltransf_31 | PF13847.13 | 3.9e-07 | 134–265 | Methyltransferase domain |
Methyltransf_11 | PF08241.19 | 2.1e-04 | 136–209 | Methyltransferase domain |
Functional interaction network (STRING v12, guilt-by-association)
Closest characterised functional partner: prfA (peptide chain release factor PrfA), high confidence from genomic context alone (score 999 excluding text-mining).
| Partner | Product | Score | No text-mining | Channels (≥400) |
|---|---|---|---|---|
Rv1299 prfA |
peptide chain release factor PrfA | 999 | 999 ctx | neighborhood:881 coexpression:896 experimental:890 textmining:551 |
Rv1301 |
threonylcarbamoyl-AMP synthase | 982 | 980 ctx | neighborhood:863 fusion:758 coexpression:440 |
Rv1307 atpH |
ATP synthase subunit b/delta | 878 | 879 ctx | neighborhood:641 coexpression:409 experimental:474 |
Rv2629 hyp |
hypothetical protein | 889 | 872 | database:844 |
Rv1305 atpE |
ATP synthase subunit C | 856 | 857 ctx | neighborhood:651 experimental:474 |
Rv1298 rpmE |
50S ribosomal protein L31 | 812 | 789 ctx | neighborhood:778 |
Rv1302 rfe |
decaprenyl-phosphate N-acetylglucosaminephosphotransferase | 777 | 777 ctx | neighborhood:770 |
Rv1304 atpB |
ATP synthase subunit A | 734 | 734 ctx | neighborhood:670 |
Rv1308 atpA |
ATP synthase subunit alpha | 714 | 714 ctx | neighborhood:428 experimental:474 |
Rv1309 atpG |
ATP synthase subunit gamma | 693 | 692 ctx | neighborhood:411 experimental:446 |
Rv1311 atpC |
ATP synthase subunit epsilon | 692 | 692 ctx | neighborhood:420 experimental:474 |
Rv1310 atpD |
ATP synthase subunit beta | 682 | 682 ctx | neighborhood:400 experimental:474 |
Rv1303 hyp |
hypothetical protein | 672 | 672 ctx | neighborhood:670 |
Rv1297 rho |
transcription termination factor Rho | 639 | 639 ctx | neighborhood:625 |
Rv1507c hyp |
hypothetical protein | 521 | 521 | experimental:446 |
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: release factor glutamine methyltransferase
- MTBC0 PGAP product: peptide chain release factor N(5)-glutamine methyltransferase
- Pfam (hmmscan --cut_ga): PrmC_N PF17827.7 (E=2e-12), MTS PF05175.21 (E=1e-05), Methyltransf_25 PF13649.13 (E=6e-08), Methyltransf_31 PF13847.13 (E=4e-07), Methyltransf_11 PF08241.19 (E=2e-04)
- (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_215816.1)
- Domains: Pfam-A via hmmscan --cut_ga — PrmC_N (PF17827.7), MTS (PF05175.21), Methyltransf_25 (PF13649.13), Methyltransf_31 (PF13847.13), Methyltransf_11 (PF08241.19)
- 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
COG2890 - Curated reference: UniProt P9WHV3 (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 —
44 functional partner(s); context anchor
prfA - Primary literature: none located yet; annotation rests on the domain/homology sources above.
Ancestral MTBC0 protein sequence
>mtbc0_001392|Rv1300|hemK MTSAPATMRWGNLPLAGESGTMTLRQAIDLAAALLAEAGVDSARCDAEQLAAHLAGTDRGRLPLFEPPGDEFFGRYRDIVTARARRVPLQHLIGTVSFGPVVLHVGPGVFVPRPETEAILAWATAQSLPARPLIVDACTGSGALAVALAQHRANLGLKARIIGIDDSDCALDYARRNAAGTPVELVRADVTTPCLLPELDGQVDLMVSNPPYIPDAAVLEPEVAQHDPHHALFGGPDGMTVISAVVGLAGRWLRPGGLFAVEHDDTTSSSTVDLVSSTKLFVDVQARKDLAGRPRFVTAMRWGHLPLAGENGAIDPRQRRCRAKR