mbtH Resolved · high auto-curated

H37Rv Rv2377c · MTBC0 mtbc0_002529 · 71 aa · 2680408–2680623 (-) · RefSeq NP_216893.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)hypothetical protein
MTBC0 PGAP re-annotationmycobactin NRPS accessory protein MbtH
Revised (this work)Mycobactin NRPS accessory protein MbtH. Pfam: MbtH (PF03621.19).

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

Curated reference (UniProt)

UniProt P9WIP5 SwissProt · reviewed · Evidence at protein level
UniProt nameProtein MbtH
Curated functionCould be involved in mycobactin synthesis.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category S Function unknown
Preferred namembtH
eggNOG descriptionprotein conserved in bacteria
Orthologous groupCOG3251
KEGG orthology K05375, K16227
KEGG pathways map00261, map01130
KEGG modules M00736

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 0.278 · purifying
Polymorphic sites (≥ 0.1% of strains) 1 synonymous, 1 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
MbtHPF03621.19 1.2e-293–53 MbtH-like protein

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

Closest characterised functional partner: pks13 (polyketide synthase), high confidence from genomic context alone (score 1000 excluding text-mining). This association is the citable seed of a function hypothesis for this hypothetical protein.

PartnerProductScoreNo text-miningChannels (≥400)
Rv3800c pks13 polyketide synthase 999 1000 ctx neighborhood:400 coexpression:915 experimental:999 textmining:496
Rv2380c mbtE peptide synthetase 999 1000 ctx neighborhood:799 cooccurence:754 coexpression:887 experimental:972 textmining:835
Rv2383c mbtB phenyloxazoline synthase 999 999 ctx neighborhood:756 cooccurence:650 coexpression:971 experimental:564 textmining:864
Rv2379c mbtF peptide synthetase 999 997 ctx neighborhood:834 cooccurence:763 coexpression:867 experimental:564 textmining:847
Rv2378c mbtG L-lysine N6-monooxygenase 996 990 ctx neighborhood:882 coexpression:915 textmining:701
Rv0101 nrp peptide synthetase Nrp 955 942 ctx cooccurence:753 coexpression:431 experimental:564
Rv2384 mbtA 2,3-dihydroxybenzoate-AMP ligase 980 931 ctx neighborhood:450 cooccurence:492 coexpression:774 textmining:724
Rv3824c papA1 acyltransferase 762 747 coexpression:426 experimental:564
Rv1182 papA3 acyltransferase papA3 761 747 coexpression:424 experimental:564
Rv3820c papA2 trehalose-2-sulfate acyltransferase 760 746 coexpression:422 experimental:564
Rv2928 tesA thioesterase TesA 754 719 ctx cooccurence:598
Rv2382c mbtC polyketide synthetase 926 699 ctx neighborhood:614 textmining:765
Rv1528c papA4 polyketide synthase associated protein PapA 710 692 coexpression:419 experimental:475
Rv1125 hyp hypothetical protein 710 692 coexpression:419 experimental:475
Rv2381c mbtD polyketide synthetase 864 606 ctx neighborhood:502 textmining:669

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: mycobactin NRPS accessory protein MbtH
  • Pfam (hmmscan --cut_ga): MbtH PF03621.19 (E=1e-29)
  • (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_216893.1)
  • Domains: Pfam-A via hmmscan --cut_ga — MbtH (PF03621.19)
  • 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 COG3251
  • Curated reference: UniProt P9WIP5 (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 — 40 functional partner(s); context anchor pks13
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002529|Rv2377c|mbtH
MSTNPFDDDNGAFFVLVNDEDQHSLWPVFADIPAGWRVVHGEASRAACLDYVEKNWTDLRPKSLRDAMAED