etgB Resolved · high auto-curated

H37Rv Rv3703c · MTBC0 mtbc0_003925 · 425 aa · 4169562–4170839 (-) · RefSeq NP_218220.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)iron(II)-dependent oxidoreductase EgtB
MTBC0 PGAP re-annotationergothioneine biosynthesis protein EgtB
Revised (this work)Ergothioneine biosynthesis protein EgtB. Pfam: DinB_2 (PF12867.13), FGE-sulfatase (PF03781.23).

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

Curated reference (UniProt)

UniProt O69671 SwissProt · reviewed · Evidence at protein level
UniProt nameHercynine oxygenase
EC (curated) EC 1.14.99.50
Curated functionCatalyzes the oxidative sulfurization of hercynine (N-alpha,N-alpha,N-alpha-trimethyl-L-histidine) into hercynyl-gamma-L-glutamyl-L-cysteine 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 nameegtB
eggNOG descriptionCatalyzes the oxidative sulfurization of hercynine (N- alpha,N-alpha,N-alpha-trimethyl-L-histidine) into hercynyl-gamma- L-glutamyl-L-cysteine sulfoxide, a step in the biosynthesis pathway of ergothioneine
Orthologous groupCOG1262
EC number EC 1.14.99.50
KEGG orthology K18912
KEGG pathways map00340
Gene Ontology (70) GO:0000096, GO:0000097, GO:0003674, GO:0003824, GO:0005488, GO:0005506, GO:0006082, GO:0006520, GO:0006547, GO:0006548, GO:0006575, GO:0006577 +58 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 0.425 · purifying
Polymorphic sites (≥ 0.1% of strains) 4 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
DinB_2PF12867.13 5.4e-1111–137 DinB superfamily
FGE-sulfatasePF03781.23 1.4e-67166–423 Sulfatase-modifying factor enzyme 1-like domain

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

Closest characterised functional partner: egtD (histidine-specific methyltransferase EtgD), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3701c egtD histidine-specific methyltransferase EtgD 999 1000 ctx neighborhood:881 fusion:893 cooccurence:773 coexpression:811 database:900 textmining:745
Rv3702c egtC amidohydrolase EgtC 999 999 ctx neighborhood:881 cooccurence:681 coexpression:860 database:900 textmining:412
Rv3704c gshA glutamate--cysteine ligase 997 992 ctx neighborhood:881 cooccurence:410 coexpression:797 database:500 textmining:745
Rv3700c egtE pyridoxal-phosphate-dependent protein EgtE 968 882 ctx neighborhood:839 textmining:745
Rv3705c hyp hypothetical protein 557 557 ctx neighborhood:543
Rv0433 carboxylate-amine ligase 513 513 database:500
Rv3299c atsB arylsulfatase AtsB 465 465 experimental:430
Rv0663 atsD arylsulfatase AtsD 451 452 experimental:430
Rv3077 hydrolase 451 451 experimental:430
Rv0711 atsA arylsulfatase AtsA 450 450 experimental:430
Rv0296c sulfatase 448 448 experimental:430
Rv2378c mbtG L-lysine N6-monooxygenase 450 424 coexpression:405
Rv1464 csd cysteine desulfurase 604 253 textmining:492
Rv3778c aminotransferase 422 185
Rv1385 pyrF orotidine 5'-phosphate decarboxylase 967 90 textmining:965

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: iron(II)-dependent oxidoreductase EgtB
  • MTBC0 PGAP product: ergothioneine biosynthesis protein EgtB
  • Pfam (hmmscan --cut_ga): DinB_2 PF12867.13 (E=5e-11), FGE-sulfatase PF03781.23 (E=1e-67)
  • (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_218220.1)
  • Domains: Pfam-A via hmmscan --cut_ga — DinB_2 (PF12867.13), FGE-sulfatase (PF03781.23)
  • 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 COG1262
  • Curated reference: UniProt O69671 (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 — 25 functional partner(s); context anchor egtD
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003925|Rv3703c|etgB
MTSPEQLACHLARARARTLRLVDFDDAELCCQYDPLMSPLVWDLAHIGQQEELWLLRGGDPGQPGLLPPAVEGLYDAFEHSRASRVELPLLSPARARSYCATVRSAALDALAALPEDGDSFVFAMVISHENQHDETMLQALNLRTGSPLLAATSALPAGRPRMAGTSVLVAGGPFVLGVDAADEPCSLDNERPAHVVDVPAFRIGRVPVTNGEWQDFIDDGGYTQSRWWSERGWQHRQRAGLTAPQFWRSGGRTRTRFGHVEDIPADEPVQHVSYFEAEAYAAWAGARLPTEVEWEKACAWDPATGSRRRYPWGTEEPTDTYANLGGQTLRPAPVGAYPAGASACGAEQMLGDVWEWTTSPLRPWPGFVPMVYERYSQPFFGGDYRVLRGGSWAVEPAILRPSFRNWDHPYRRQIFAGVRLAWDI