mshD Resolved · high auto-curated

H37Rv Rv0819 · MTBC0 mtbc0_000868 · 315 aa · 914803–915750 (+) · RefSeq NP_215334.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)mycothiol acetyltransferase
MTBC0 PGAP re-annotationmycothiol synthase
Revised (this work)Mycothiol synthase. Pfam: Acetyltransf_1 (PF00583.32), Acetyltransf_7 (PF13508.14).

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

Curated reference (UniProt)

UniProt P9WJM7 SwissProt · reviewed · Evidence at protein level
UniProt nameMycothiol acetyltransferase
EC (curated) EC 2.3.1.189
Curated functionCatalyzes the transfer of acetyl from acetyl-CoA to desacetylmycothiol (Cys-GlcN-Ins) to form mycothiol.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category K Transcription
Preferred namemshD
eggNOG descriptionCatalyzes the transfer of acetyl from acetyl-CoA to desacetylmycothiol (Cys-GlcN-Ins) to form mycothiol
Orthologous groupCOG0454
EC number EC 2.3.1.189
KEGG orthology K15520
Gene Ontology (73) GO:0000302, GO:0003674, GO:0003824, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0005829, GO:0006790, GO:0006950, GO:0006979, GO:0008080 +61 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 0.285 · purifying
Polymorphic sites (≥ 0.1% of strains) 4 synonymous, 3 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
Acetyltransf_1PF00583.32 1.2e-0646–111 Acetyltransferase (GNAT) family
Acetyltransf_7PF13508.14 4.9e-0648–109 Acetyltransferase (GNAT) domain

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

Closest characterised functional partner: Rv0818 (transcriptional regulator), high confidence from genomic context alone (score 884 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv0818 transcriptional regulator 888 884 ctx neighborhood:882
Rv2984 ppk1 polyphosphate kinase 815 815 ctx fusion:783
Rv2466c hyp hypothetical protein 798 799 ctx cooccurence:769
Rv2130c mshC cysteine:1D-myo-inosityl 2-amino-2-deoxy--D-glucopyranoside ligase 989 777 ctx cooccurence:549 database:500 textmining:955
Rv1998c hyp hypothetical protein 767 768 coexpression:768
Rv1082 mca mycothiol S-conjugate amidase 936 767 ctx cooccurence:763 textmining:739
Rv2553c mltG membrane protein 735 736 coexpression:735
Rv0360c hyp hypothetical protein 696 696 ctx cooccurence:693
Rv1170 mshB 1D-myo-inositol 2-acetamido-2-deoxy-alpha-D-glucopyranoside deacetylase 984 694 ctx cooccurence:691 textmining:953
Rv0820 phoT phosphate ABC transporter ATP-binding protein PhoT 809 690 ctx neighborhood:680 textmining:412
Rv2286c hyp hypothetical protein 649 650 ctx cooccurence:646
Rv0817c lmeA hyp hypothetical protein 753 624 ctx neighborhood:624
Rv0486 mshA D-inositol 3-phosphate glycosyltransferase 972 610 ctx cooccurence:610 textmining:932
Rv0816c thiX thioredoxin ThiX 802 591 ctx neighborhood:591 textmining:537
Rv2133c hyp hypothetical protein 513 514 ctx cooccurence:507

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: mycothiol acetyltransferase
  • MTBC0 PGAP product: mycothiol synthase
  • Pfam (hmmscan --cut_ga): Acetyltransf_1 PF00583.32 (E=1e-06), Acetyltransf_7 PF13508.14 (E=5e-06)
  • (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_215334.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Acetyltransf_1 (PF00583.32), Acetyltransf_7 (PF13508.14)
  • 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 COG0454
  • Curated reference: UniProt P9WJM7 (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 — 48 functional partner(s); context anchor Rv0818
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_000868|Rv0819|mshD
MTALDWRSALTADEQRSVRALVTATTAVDGVAPVGEQVLRELGQQRTEHLLVAGSRPGGPIIGYLNLSPPRGAGGAMAELVVHPQSRRRGIGTAMARAALAKTAGRNQFWAHGTLDPARATASALGLVGVRELIQMRRPLRDIPEPTIPDGVVIRTYAGTSDDAELLRVNNAAFAGHPEQGGWTAVQLAERRGEAWFDPDGLILAFGDSPRERPGRLLGFHWTKVHPDHPGLGEVYVLGVDPAAQRRGLGQMLTSIGIVSLARRLGGRKTLDPAVEPAVLLYVESDNVAAVRTYQSLGFTTYSVDTAYALAGTDN