Rv1990c Family assigned · medium auto-curated

H37Rv Rv1990c · MTBC0 mtbc0_002114 · 113 aa · 2256909–2257250 (-) · RefSeq NP_216506.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)transcriptional regulator
MTBC0 PGAP re-annotationantitoxin Xre/MbcA/ParS toxin-binding domain-containing protein
Revised (this work)Antitoxin Xre/MbcA/ParS toxin-binding domain-containing protein. Pfam: Xre_MbcA_ParS_C (PF09722.16).

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

Curated reference (UniProt)

UniProt P9WLP7 SwissProt · reviewed · Evidence at protein level
UniProt nameMycobacterial cidal antitoxin MbcA
Curated functionAntitoxin component of a type II toxin-antitoxin (TA) system. Neutralizes the activity of cognate toxin MbcT by blocking access to the toxin active site.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category K Transcription
eggNOG descriptionProtein of unknown function (DUF2384)
Orthologous group2AF64

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 0.0 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 0 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
Xre_MbcA_ParS_CPF09722.16 1.7e-0763–110 Antitoxin Xre/MbcA/ParS C-terminal toxin-binding domain

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

Closest characterised functional partner: Rv1990A (Rv1990A, len: 111 aa. Possible dehydrogenase (fragment), similar to N-terminal part of several dehydrogenases and hypothetical proteins, e.g), medium confidence from genomic context alone (score 430 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv1989c mbcT hyp hypothetical protein 999 1000 ctx neighborhood:882 experimental:999 textmining:870
Rv1990A Rv1990A, len: 111 aa. Possible dehydrogenase (fragment), similar to N-terminal part of several dehydrogenases and hypothetical proteins, e.g 430 430 ctx neighborhood:425
Rv2034 ArsR family HTH-type transcriptional repressor 644 85 textmining:627
Rv2021c higA2 transcriptional regulator 533 85 textmining:511
Rv0691c mftR mycofactocin biosynthesis transcriptional regulator MftR 440 55 textmining:432
Rv0238 transcriptional regulator 653 47 textmining:651
Rv1423 whiA transcriptional regulator WhiA 433 45 textmining:431
Rv0023 transcriptional regulator 861 42 textmining:861
Rv2862A vapB23 antitoxin VapB23 440 41 textmining:440

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: transcriptional regulator
  • MTBC0 PGAP product: antitoxin Xre/MbcA/ParS toxin-binding domain-containing protein
  • Pfam (hmmscan --cut_ga): Xre_MbcA_ParS_C PF09722.16 (E=2e-07)
  • (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_216506.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Xre_MbcA_ParS_C (PF09722.16)
  • 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 2AF64
  • Curated reference: UniProt P9WLP7 (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 — 9 functional partner(s); context anchor Rv1990A
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002114|Rv1990c|
MGVNVLASTVSGAIERLGLTYEEVGDIVDASPRSVARWTAGQVVPQRLNKQRLIELAYVADALAEVLPRDQANVWMFSPNRLLEHRKPADLVRDGEYQRVLALIDAMAEGVFV