ift Resolved · high auto-curated

H37Rv Rv3902c · MTBC0 mtbc0_004136 · 176 aa · 4411617–4412147 (-) · RefSeq NP_218419.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationnecrotizing toxin immunity factor IFT
Revised (this work)Necrotizing toxin immunity factor IFT. Pfam: Imm61 (PF15598.12).

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

Curated reference (UniProt)

UniProt O05443 SwissProt · reviewed · Evidence at protein level
UniProt nameImmunity factor for TNT
Curated functionAntitoxin for tuberculosis necrotizing toxin (TNT). Acts by binding directly to TNT, which inhibits NAD(+) glycohydrolase activity of TNT and protects M.tuberculosis from self-poisoning.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionImmunity protein 61
Orthologous group2DEW1

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 0.205 · purifying
Polymorphic sites (≥ 0.1% of strains) 3 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)

PfamAccessioni-EvalueResiduesDescription
Imm61PF15598.12 3.1e-6514–167 Immunity protein 61

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

Closest characterised functional partner: esxE (ESAT-6 like protein EsxE), high confidence from genomic context alone (score 883 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv3903c cpnT hyp hypothetical protein 996 978 ctx neighborhood:882 experimental:817 textmining:870
Rv3904c esxE ESAT-6 like protein EsxE 941 883 ctx neighborhood:882 textmining:522
Rv3905c esxF ESAT-6 like protein EsxF 953 881 ctx neighborhood:880 textmining:630
Rv3899c hyp hypothetical protein 662 663 experimental:652
Rv2082 hyp hypothetical protein 662 663 experimental:652
Rv3906c hyp hypothetical protein 970 634 ctx neighborhood:629 textmining:922
Rv3907c pcnA poly(A) polymerase PcnA 583 583 ctx neighborhood:582
Rv3884c eccA2 ESX-2 secretion system protein EccA 523 51 textmining:518
Rv3896c hyp hypothetical protein 804 47 textmining:803
Rv0152c PE2 PE family protein PE2 433 41 textmining:433

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: necrotizing toxin immunity factor IFT
  • Pfam (hmmscan --cut_ga): Imm61 PF15598.12 (E=3e-65)
  • (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_218419.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Imm61 (PF15598.12)
  • 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 2DEW1
  • Curated reference: UniProt O05443 (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 — 10 functional partner(s); context anchor esxE
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_004136|Rv3902c|ift
MTIGVDLSTDLQDWIRLSGMNMIQGSETNDGRTILWNKGGEVRYFIDRLAGWYVITSSDRMSREGYEFAAASMSVIEKYLYGYFGGSVRSERELPAIRAPFQPEELMPEYSIGTMTFAGRQRDTLIDSSGTVVAITAADRLVELSHYLDVSVNVIKDSFLDSEGKPLFTLWKDYKG