vapC43 Family assigned · medium auto-curated

H37Rv Rv2872 · MTBC0 mtbc0_003054 · 147 aa · 3204048–3204491 (+) · RefSeq NP_217388.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)ribonuclease VapC43
MTBC0 PGAP re-annotationtype II toxin-antitoxin system VapC family toxin
Revised (this work)Type II toxin-antitoxin system VapC family toxin. Pfam: PIN (PF01850.28).

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

Curated reference (UniProt)

UniProt P9WF55 SwissProt · reviewed · Evidence at protein level
UniProt nameRibonuclease VapC43
EC (curated) EC 3.1.-.-
Curated functionToxic component of a type II toxin-antitoxin (TA) system. An RNase (By similarity). Upon expression in M.smegmatis inhibits colony formation. Its toxic effect is neutralized by coexpression with cognate antitoxin VapB43.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionToxic component of a toxin-antitoxin (TA) module. An RNase
Orthologous groupCOG1848
KEGG orthology K07064
Gene Ontology (6) GO:0008150, GO:0040008, GO:0045926, GO:0048519, GO:0050789, GO:0065007

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 0.677 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 2 missense, 0 nonsense, 1 frameshift
Disruption 1 distinct premature-stop/frameshift site(s); most common in 0.13% of strains (182) · 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
PINPF01850.28 3.2e-163–134 PIN domain

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

Closest characterised functional partner: vapB43 (antitoxin VapB43), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2871 vapB43 antitoxin VapB43 999 1000 ctx neighborhood:800 experimental:999 textmining:803
Rv2873 mpt83 cell surface lipoprotein 617 617 ctx neighborhood:605
Rv2870c dxr 1-deoxy-D-xylulose 5-phosphate reductoisomerase 545 545 ctx neighborhood:543
Rv2869c rip zinc metalloprotease 542 542 ctx neighborhood:542
Rv0595c vapC4 ribonuclease VapC4 760 527 ctx cooccurence:517 textmining:514
Rv0748 vapB31 antitoxin VapB31 524 524 experimental:508
Rv2868c gcpE 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase (flavodoxin) 519 519 ctx neighborhood:519
Rv1720c vapC12 ribonuclease VapC12 495 496 ctx cooccurence:491
Rv0626 vapB5 antitoxin VapB5 476 476 ctx cooccurence:465
Rv0960 vapC9 ribonuclease VapC9 448 448 ctx cooccurence:448
Rv2548 vapC19 ribonuclease VapC19 653 432 ctx cooccurence:430 textmining:414
Rv2867c GCN5-like N-acetyltransferase 415 415 ctx neighborhood:414
Rv0743c hyp hypothetical protein 414 415 ctx cooccurence:411
Rv1397c vapC10 ribonuclease VapC10 641 394 textmining:433
Rv2549c vapC20 ribonuclease VapC20 659 320 textmining:520

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: ribonuclease VapC43
  • MTBC0 PGAP product: type II toxin-antitoxin system VapC family toxin
  • Pfam (hmmscan --cut_ga): PIN PF01850.28 (E=3e-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_217388.1)
  • Domains: Pfam-A via hmmscan --cut_ga — PIN (PF01850.28)
  • 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 COG1848
  • Curated reference: UniProt P9WF55 (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 — 23 functional partner(s); context anchor vapB43
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003054|Rv2872|vapC43
MLCVDVNVLVYAHRADLREHADYRGLLERLANDDEPLGLPDSVLAGFIRVVTNRRVFTEPTSPQDAWQAVDALLAAPAAMRLRPGERHWMAFRQLASDVDANGNDIADAHLAAYALENNATWLSADRGFARFRRLRWRHPLDGQTHL