egtC Resolved · high auto-curated

H37Rv Rv3702c · MTBC0 mtbc0_003924 · 233 aa · 4168861–4169562 (-) · RefSeq NP_218219.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)amidohydrolase EgtC
MTBC0 PGAP re-annotationergothioneine biosynthesis protein EgtC
Revised (this work)Ergothioneine biosynthesis protein EgtC. Pfam: GATase_4 (PF13230.12).

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

Curated reference (UniProt)

UniProt O69670 SwissProt · reviewed · Evidence at protein level
UniProt nameGamma-glutamyl-hercynylcysteine sulfoxide hydrolase
EC (curated) EC 3.5.1.118
Curated functionCatalyzes the hydrolysis of the gamma-glutamyl amide bond of hercynyl-gamma-L-glutamyl-L-cysteine sulfoxide to produce hercynylcysteine sulfoxide, a step in the biosynthesis pathway of ergothioneine. Ergothioneine is an antioxidant that protects mycobacteria from oxidative stress.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred nameegtC
eggNOG descriptionCatalyzes the hydrolysis of the gamma-glutamyl amide bond of hercynyl-gamma-L-glutamyl-L-cysteine sulfoxide to produce hercynylcysteine sulfoxide, a step in the biosynthesis pathway of ergothioneine
Orthologous groupCOG0121
EC number EC 3.5.1.118
KEGG orthology K07008
KEGG pathways map00340
Gene Ontology (81) GO:0000096, GO:0000097, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005886, GO:0006082, GO:0006518, GO:0006520, GO:0006547, GO:0006548 +69 more

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 0.145 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 5 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
GATase_4PF13230.12 5.9e-0928–118 Glutamine amidotransferases class-II

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

Closest characterised functional partner: etgB (iron(II)-dependent oxidoreductase EgtB), high confidence from genomic context alone (score 999 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3703c etgB iron(II)-dependent oxidoreductase EgtB 999 999 ctx neighborhood:881 cooccurence:681 coexpression:860 database:900 textmining:412
Rv3701c egtD histidine-specific methyltransferase EtgD 996 995 ctx neighborhood:882 fusion:577 cooccurence:472 coexpression:819
Rv3700c egtE pyridoxal-phosphate-dependent protein EgtE 996 992 ctx neighborhood:839 coexpression:441 database:900 textmining:598
Rv3704c gshA glutamate--cysteine ligase 988 988 ctx neighborhood:882 cooccurence:631 coexpression:748
Rv3705c hyp hypothetical protein 575 575 ctx neighborhood:555
Rv3707c hyp hypothetical protein 414 414
Rv1464 csd cysteine desulfurase 400 156

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: amidohydrolase EgtC
  • MTBC0 PGAP product: ergothioneine biosynthesis protein EgtC
  • Pfam (hmmscan --cut_ga): GATase_4 PF13230.12 (E=6e-09)
  • (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_218219.1)
  • Domains: Pfam-A via hmmscan --cut_ga — GATase_4 (PF13230.12)
  • 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 COG0121
  • Curated reference: UniProt O69670 (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 — 7 functional partner(s); context anchor etgB
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003924|Rv3702c|egtC
MCRHLGWLGAQVAVSSLVLDPPQGLRVQSYAPRRQKHGLMNADGWGVGFFDGAIPRRWRSPAPLWGDTSFHSVAPALRSHCILAAVRSATVGMPIEVSATPPFTDGHWLLAHNGVVDRAVLPAGPAAESVCDSAILAATIFAHGLDALGDTIVKVGAADPNARLNILAANGSRLIATTWGDTLSILRRADGVVLASEPYDDDSGWGDVPDRHLVEVTQKGVTLTALDRAKGPR