Rv2422 Family assigned · low

H37Rv Rv2422 · MTBC0 mtbc0_002579 · 90 aa · 2743351–2743623 (+) · RefSeq NP_216938.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationhypothetical protein
Revised (this work)Predicted toxin of a type II toxin-antitoxin (TA) system (eggNOG COG1848). RefSeq leaves it 'hypothetical protein'. Note: the Rv2421c-Rv2422 region also harbours a cryptic beta-lactam-binding ORF (Kumar 2017); the eggNOG orthology points to a TA-toxin fold for Rv2422 itself. Family-level; the cognate antitoxin and activity are undetermined.

Curated reference (UniProt)

UniProt P71926 TrEMBL · unreviewed · Predicted
UniProt nameUncharacterized protein

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

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionToxic component of a toxin-antitoxin (TA) module. An RNase
Orthologous groupCOG1848

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 0.376 · purifying
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 1 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)

No Pfam-A domain above the gathering threshold (or not yet scanned).

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

Closest characterised functional partner: gpgP (glucosyl-3-phosphoglycerate phosphatase), medium confidence from genomic context alone (score 477 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv2419c gpgP glucosyl-3-phosphoglycerate phosphatase 477 477 ctx neighborhood:477
Rv0620 galK galactokinase 457 458 coexpression:458
Rv2421c nadD nicotinate-nucleotide adenylyltransferase 787 449 ctx neighborhood:449 textmining:630
Rv2418c octT hyp hypothetical protein 449 449 ctx neighborhood:449
Rv2420c rsfS hyp hypothetical protein 449 449 ctx neighborhood:449
Rv2423 hyp hypothetical protein 428 428 ctx neighborhood:425
Rv0449c hyp hypothetical protein 441 47 textmining:438
Rv3160c TetR family transcriptional regulator 517 44 textmining:516
Rv3240c secA1 protein translocase subunit SecA 413 44 textmining:412
Rv2068c blaC beta-lactamase 543 41 textmining:543

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

  • eggNOG COG1848 = toxic component of a toxin-antitoxin system
  • eggNOG-mapper orthology (COG functional assignment, under-propagated by the auto-curation). A family/activity-level assignment from orthology, not a substrate demonstrated in M. tuberculosis.

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_216938.1)
  • Domains: Pfam-A via hmmscan --cut_ga — none above threshold
  • 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 P71926 (TrEMBL, unreviewed; 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 — 10 functional partner(s); context anchor gpgP
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002579|Rv2422|
MPASVSTVLVDTSVAVAPVVADHDHHEDTFQALRGRTLGLAGHAAFERRTLATVAKLLAHTFPATRFLGAGAAMSLLPELAPAEIAGGAV