Rv0543c Family assigned · medium

H37Rv Rv0543c · MTBC0 mtbc0_000572 · 100 aa · 639124–639426 (-) · RefSeq NP_215057.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationDUF3349 domain-containing protein
Revised (this work)Member of the DUF3349 (PF11829) protein superfamily, found predominantly in Mycobacterium and Rhodococcus. The inaugural DUF3349 structure was solved for Rv0543c by NMR: a monomeric five-alpha-helix bundle (Buchko 2011); comparative structures show two structural subfamilies (Buchko 2020). Biological function unknown but family-restricted to these genera.

Curated reference (UniProt)

UniProt O06409 TrEMBL · unreviewed · Evidence at protein level
UniProt nameConserved protein

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

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
eggNOG descriptionProtein of unknown function (DUF3349)
Orthologous group2E7QJ

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 0.662 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 1 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
DUF3349PF11829.14 1.1e-334–92 Protein of unknown function (DUF3349)

Structural neighbours (Foldseek on the ESMFold model, exploratory)

ESMFold model confidence: mean pLDDT 63.1 (low). Low-confidence model: the fold may be unreliable, so treat these structural hits with caution.

Best matches against the PDB, ranked by Foldseek homology probability. A high probability / TM-score suggests a shared fold; unless flagged sig (E < 0.01) these are fold hypotheses, not assignments.

TargetProbTME-valueDescription
2kvc-assembly1_A 1.00 0.83 8.4e-12 sig 2kvc-assembly1_A Solution structure of the Mycobacterium tuberculosis protein Rv0543c, a member of the DUF3349 superfamily. Seattle Structural Genomics Center for Infectious Disease target MytuD.17112.a
2lky-assembly1_A 1.00 0.73 1.5e-07 sig 2lky-assembly1_A Solution structure of MSMEG_1053, the second DUF3349 annotated protein in the genome of Mycobacterium smegmatis, Seattle Structural Genomics Center for Infectious Disease target MysmA.17112.b
5m30-assembly1_A 0.01 0.20 5.9e+00 5m30-assembly1_A Structure of TssK from T6SS EAEC in complex with nanobody nb18

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

Closest characterised functional partner: pitA (low-affinity inorganic phosphate transporter), high confidence from genomic context alone (score 848 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv0545c pitA low-affinity inorganic phosphate transporter 848 848 ctx neighborhood:803
Rv0544c transmembrane protein 808 808 ctx neighborhood:803
Rv0542c menE 2-succinylbenzoic acid--CoA ligase 806 807 ctx neighborhood:795
Rv0541c integral membrane protein 797 797 ctx neighborhood:792
Rv0547c oxidoreductase 514 515 ctx neighborhood:512
Rv0184 hyp hypothetical protein 497 497 ctx cooccurence:494
Rv0185 hyp hypothetical protein 479 480 ctx cooccurence:475
Rv3804c fbpA diacylglycerol acyltransferase/mycolyltransferase Ag85A 439 439 ctx cooccurence:432
Rv3256c hyp hypothetical protein 436 436 ctx cooccurence:428
Rv3454 Rv3454, (MTCY13E12.07), len: 422 aa. Probable conserved integral membrane protein, showing some similarity to various proteins (generally tr 435 436 ctx cooccurence:432
Rv0129c fbpC diacylglycerol acyltransferase/mycolyltransferase Ag85C 431 432 ctx cooccurence:428
Rv0546c hyp hypothetical protein 410 410 ctx neighborhood:406

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

  • Inaugural DUF3349 superfamily NMR structure: 5-alpha-helix bundle (Buchko 2011, PMID 21144816)
  • DUF3349 has two structural subfamilies; Mycobacterium/Rhodococcus-restricted (Buchko 2020, PMID 31658388)
  • Curated from the literature crible (project 'Still unknown gene function', 2026-06-09)

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_215057.1)
  • Domains: Pfam-A via hmmscan --cut_ga — DUF3349 (PF11829.14)
  • 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 2E7QJ
  • Curated reference: UniProt O06409 (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)
  • Model confidence: ESMFold per-residue pLDDT (mean 63.1, low)
  • Interaction network: STRING v12.0 (Szklarczyk et al. 2023, doi:10.1093/nar/gkac1000), taxon 83332, CC-BY 4.0 — 12 functional partner(s); context anchor pitA
  • Primary literature: Buchko GW, Phan I, Myler PJ, Terwilliger TC, Kim CY (2011). Inaugural structure from the DUF3349 superfamily of proteins, Mycobacterium tuberculosis Rv0543c Arch Biochem Biophys 506(2):150-6. doi:10.1016/j.abb.2010.12.001 PMID:21144816

Ancestral MTBC0 protein sequence

>mtbc0_000572|Rv0543c|
MNRFLTSIVAWLRAGYPEGIPPTDSFAVLALLCRRLSHDEVKAVANELMRLGDFDQIDIGVVITHFTDELPSPEDVERVRARLAAQGWPLDDVRDREEHA