Rv0918 Family assigned · medium auto-curated

H37Rv Rv0918 · MTBC0 mtbc0_000975 · 158 aa · 1027426–1027902 (+) · RefSeq NP_215433.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationDUF1778 domain-containing protein
Revised (this work)DUF1778 domain-containing protein. Pfam: TacA1 (PF08681.19).

Auto-curated: this verdict and function were generated by rules from PGAP + Pfam + Foldseek and have not been hand-reviewed.

Curated reference (UniProt)

UniProt O05910 SwissProt · reviewed · Evidence at transcript level
UniProt nameAntitoxin TacA
Curated functionAntitoxin component of a type II toxin-antitoxin (TA) system. Counteracts the toxic effect of cognate toxin TacT..; FUNCTION: TacA-TacT both represses and derepresses expression of its own operon.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionProtein of unknown function (DUF1778)
Orthologous groupCOG4453

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 1.821 · diversifying/relaxed
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 4 missense, 1 nonsense, 0 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.64% of strains (933) · clonal

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)

PfamAccessioni-EvalueResiduesDescription
TacA1PF08681.19 5.0e-2674–150 Antitoxin TacA 1-like

Functional interaction network (STRING v12, guilt-by-association)

Closest characterised functional partner: Rv0919 (GCN5-like N-acetyltransferase), high confidence from genomic context alone (score 973 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv0919 GCN5-like N-acetyltransferase 973 973 ctx neighborhood:801 cooccurence:767 experimental:451
Rv0240 vapC24 ribonuclease VapC24 682 682 ctx cooccurence:681
Rv2775 GCN5-like N-acetyltransferase 615 613 experimental:451
Rv1525 wbbL2 rhamnosyl transferase WbbL 510 511 ctx cooccurence:510
Rv0133 GCN5-like N-acetyltransferase 478 479 experimental:449
Rv2170 GCN5-like N-acetyltransferase 474 472 experimental:451
Rv2669 GCN5-like N-acetyltransferase 472 470 experimental:451
Rv0355c PPE8 PPE family protein PPE8 470 470 ctx cooccurence:467
Rv3420c rimI ribosomal-protein-alanine acetyltransferase RimI 470 468 experimental:451
Rv0428c GCN5-like N-acetyltransferase 470 468 experimental:451
Rv0819 mshD mycothiol acetyltransferase 470 468 experimental:451
Rv0304c PPE5 PPE family protein PPE5 468 468 ctx cooccurence:465
Rv3347c PPE55 PPE family protein PPE55 465 465 ctx cooccurence:462
Rv3350c PPE56 PPE family protein PPE56 463 464 ctx cooccurence:462
Rv2949c chorismate pyruvate-lyase 456 456 ctx cooccurence:455

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: hypothetical protein
  • MTBC0 PGAP product: DUF1778 domain-containing protein
  • Pfam (hmmscan --cut_ga): TacA1 PF08681.19 (E=5e-26)
  • (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_215433.1)
  • Domains: Pfam-A via hmmscan --cut_ga — TacA1 (PF08681.19)
  • 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 COG4453
  • Curated reference: UniProt O05910 (SwissProt, reviewed; Evidence at transcript 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 — 47 functional partner(s); context anchor Rv0919
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_000975|Rv0918|
MHRAGAAVTANVWCRAGGIRMAPRPVIPVATQQRLRRQADRQSLGGSGLPALNCTPIRHTIDVMATKPERKTERLAARLTPEQDALIRRAAEAEGTDLTNFTVTAALAHARDVLADRRLFVLTDAAWTEFLAALDRPVSHKPRLEKLFAARSIFDTEG