Rv3439c Family assigned · medium

H37Rv Rv3439c · MTBC0 mtbc0_003658 · 467 aa · 3884145–3885548 (-) · RefSeq NP_217956.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationhypothetical protein
Revised (this work)ESAT-6-like (WXG100) / ESX-PE-PPE superfamily protein associated with the Type VII (ESX) secretion system; conserved four-helical-bundle/WXG domain within a large (467 aa) protein RefSeq leaves this locus uncharacterised.

Curated reference (UniProt)

UniProt I6YC49 TrEMBL · unreviewed · Evidence at protein level
UniProt nameConserved hypothetical alanine and proline rich protein

Functional vocabulary (eggNOG-mapper, orthology transfer)

Orthologous group2ANA8

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 0.239 · purifying
Polymorphic sites (≥ 0.1% of strains) 9 synonymous, 6 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: mrsA (phosphoglucosamine mutase), high confidence from genomic context alone (score 822 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv3440c hyp hypothetical protein 932 932 ctx neighborhood:882 coexpression:449
Rv3441c mrsA phosphoglucosamine mutase 822 822 ctx neighborhood:816
Rv3903c cpnT hyp hypothetical protein 732 732 coexpression:732
Rv2759c vapC42 ribonuclease VapC42 730 730 coexpression:730
Rv2760c vapB42 antitoxin VapB42 703 703 coexpression:703
Rv3442c rpsI 30S ribosomal protein S9 524 524 ctx neighborhood:519
Rv3444c esxT ESAT-6 like protein EsxT 513 513
Rv3443c rplM 50S ribosomal protein L13 450 450 ctx neighborhood:445
Rv3911 sigM ECF RNA polymerase sigma factor SigM 449 449 coexpression:449
Rv3657c membrane protein 441 441 coexpression:441

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

  • HHpred (significant): 16 concordant top hits all ESX/ESAT-6 family ~97.8-98.1%, E 1.6e-4 to 2e-3 (ESXS, ESAT-6/EsxA 3FAV, EsxR, EsxB, PE family, MAB_3112/3113); aligned over the ~90-col conserved domain
  • HHpred web (MPI Bioinformatics Toolkit, profile-profile remote homology), interpreted in project 'Still unknown gene function', 2026-06-10. A fold/family-level assignment, not a demonstrated function.

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_217956.1)
  • 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 2ANA8
  • Curated reference: UniProt I6YC49 (TrEMBL, unreviewed; 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 mrsA
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003658|Rv3439c|
MADRLNVAERLAEGRPAAEHTQSYVRACHLVGYQHPDLTAYPAQIHDWYGSEDGLDLHALDADCAQLRAAASVLMEALRMERSQVAVLAAAWTGSGADAAVHFVQRHCETGNSVVTEVRAAAQRCESLRDNLWQLVDSKVATAIAIDERALAQRPAWLAAAEALTTEGADRPTAVEVVRQQIQPYVDDDVRNDWLTTMRSTTAGVAASYDAVTDQLASAPRAHFEIPDDLGPGRQPSPASVPAQPSATAAITPAAALPPPDPVPAVTSRPVTPSDFGSAPGDGSATPAGVGSAGGFGDAGGTGGLGGFAGLAGLANRIVDAVDSLLGSVAEQLGDPLAADNPPGAVDPFAEDAADNADDGDDAHPEEADEAAEPKEATEPDEADEVDDADESVPAERAQDVAEEATLPPVAEPPPPAAPPVAEPPPPVAAPAPPGAPEPANGPSPEALSEGATPCEIAADELPQAGP