vapB14 Resolved · high auto-curated

H37Rv Rv1952 · MTBC0 mtbc0_002067 · 71 aa · 2219842–2220057 (+) · RefSeq NP_216468.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)antitoxin VapB14
MTBC0 PGAP re-annotationantitoxin
Revised (this work)Antitoxin. Pfam: FitA-like_RHH (PF22513.3).

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

Curated reference (UniProt)

UniProt P95262 SwissProt · reviewed · Predicted
UniProt namePutative antitoxin VapB14
Curated functionPutative antitoxin component of a possible type II toxin-antitoxin (TA) system. The cognate toxin is VapB14.

UniProt still lists this protein as Putative antitoxin VapB14; the revised annotation above is ahead of the current UniProt record.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionPlasmid stability protein
Orthologous groupCOG4691
KEGG orthology K21495

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, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.10% of strains (151) · 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
FitA-like_RHHPF22513.3 1.8e-162–34 Antitoxin FitA-like, ribbon-helix-helix

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

Closest characterised functional partner: vapC14 (ribonuclease VapC14), high confidence from genomic context alone (score 926 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1953 vapC14 ribonuclease VapC14 928 926 ctx neighborhood:882
Rv1950c hyp hypothetical protein 472 472 ctx neighborhood:463
Rv1949c Rv1949c, (MTCY09F9.15), len: 319 aa. Conserved hypothetical protein, partial ORF. Rv1949c and Rv1950c|MTCY09F9.14 are similar but frameshift 467 468 ctx neighborhood:466
Rv1951c hyp hypothetical protein 466 466 ctx neighborhood:463
Rv1948c hyp hypothetical protein 463 463 ctx neighborhood:463
Rv0595c vapC4 ribonuclease VapC4 437 415
Rv0665 vapC8 ribonuclease VapC8 437 415
Rv0627 vapC5 ribonuclease VapC5 437 415
Rv1397c vapC10 ribonuclease VapC10 432 410
Rv0301 vapC2 ribonuclease VapC2 431 408
Rv2527 vapC17 ribonuclease VapC17 430 408
Rv2757c vapC21 ribonuclease VapC21 429 407
Rv2546 vapC18 ribonuclease VapC18 429 407
Rv1114 vapC32 ribonuclease VapC32 429 407
Rv0656c vapC6 ribonuclease VapC6 429 407

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: antitoxin VapB14
  • MTBC0 PGAP product: antitoxin
  • Pfam (hmmscan --cut_ga): FitA-like_RHH PF22513.3 (E=2e-16)
  • (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_216468.1)
  • Domains: Pfam-A via hmmscan --cut_ga — FitA-like_RHH (PF22513.3)
  • 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 COG4691
  • Curated reference: UniProt P95262 (SwissProt, reviewed; Predicted)
  • 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 — 34 functional partner(s); context anchor vapC14
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002067|Rv1952|vapB14
MIRNLPEGTKAALRVRAARHHHSVEAEARAILTAGLLGEEVPMPVLLAADSGHDIDFEPERLGLIARTPQL