Rv3015c Resolved · high auto-curated

H37Rv Rv3015c · MTBC0 mtbc0_003204 · 337 aa · 3395960–3396973 (-) · RefSeq NP_217531.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationmethionine synthase
Revised (this work)Methionine synthase. Pfam: Meth_synt_2 (PF01717.25).

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

Curated reference (UniProt)

UniProt I6YAW3 TrEMBL · unreviewed · Evidence at protein level
UniProt nameCobalamin-independent methionine synthase MetE C-terminal/archaeal domain-containing protein

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category E Amino acid transport and metabolism
eggNOG descriptionMethionine synthase
Orthologous groupCOG0620

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 0.658 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 3 synonymous, 5 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
Meth_synt_2PF01717.25 8.5e-824–328 Cobalamin-independent synthase, Catalytic domain

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

Closest characterised functional partner: lpqA (lipoprotein LpqA), high confidence from genomic context alone (score 783 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv3016 lpqA lipoprotein LpqA 782 783 ctx neighborhood:782
Rv2172c hyp hypothetical protein 841 765 coexpression:723
Rv3014c ligA DNA ligase A 748 748 ctx neighborhood:740
Rv1392 metK S-adenosylmethionine synthetase 736 701 coexpression:644
Rv1433 ldtMt3 hyp hypothetical protein 659 659 ctx cooccurence:658
Rv0192 hyp hypothetical protein 635 635 ctx cooccurence:635
Rv0116c ldtA L,D-transpeptidase LdtA 627 627 ctx cooccurence:627
Rv2867c GCN5-like N-acetyltransferase 624 624 ctx cooccurence:624
Rv2239c hyp hypothetical protein 614 614 ctx cooccurence:614
Rv2518c ldtB L,D-transpeptidase LdtB 611 611 ctx cooccurence:609
Rv0483 lprQ lipoprotein LprQ 590 575 ctx cooccurence:575
Rv2124c metH methionine synthase 875 574 coexpression:516 textmining:720
Rv3268 hyp hypothetical protein 574 574 ctx cooccurence:569
Rv3256c hyp hypothetical protein 573 557 ctx cooccurence:556
Rv3248c sahH adenosylhomocysteinase 586 531 coexpression:504

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: methionine synthase
  • Pfam (hmmscan --cut_ga): Meth_synt_2 PF01717.25 (E=8e-82)
  • (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_217531.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Meth_synt_2 (PF01717.25)
  • 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 COG0620
  • Curated reference: UniProt I6YAW3 (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 — 51 functional partner(s); context anchor lpqA
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003204|Rv3015c|
MSVFATATGIGSWPGTAAREAAQVVVGELAGALAYLTELPARGVGADMLGRAGGLLVDVAIDTVPRGYRIAARPGAVTRRAASLLDEDMDALEEAWETAGLRGCGRAVKVQAPGPVTLVAGLELANGHRAITDPGAVRDLAASLAEGVAAHRAALARRLDTPVVVQFDEPSLPAALGGRLTGVTALSPVAPLDETVAEALLDTCIAAVDADVALHSCSPDLPWDLLQRSRISAVSVDASTLQAADLDAVAAFVESGRTVVLGLVPVTAPERAPSMEEVAAAAVAVTDRLGVPRSALRDRLGVSPACGLANATGQWARTAVGLARDVAEAFARDPEAI