leuB Resolved · high auto-curated

H37Rv Rv2995c · MTBC0 mtbc0_003182 · 336 aa · 3373767–3374777 (-) · RefSeq NP_217511.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)3-isopropylmalate dehydrogenase
MTBC0 PGAP re-annotation3-isopropylmalate dehydrogenase
Revised (this work)3-isopropylmalate dehydrogenase. Pfam: Iso_dh (PF00180.26).

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

Curated reference (UniProt)

UniProt P9WKK9 SwissProt · reviewed · Evidence at protein level
UniProt name3-isopropylmalate dehydrogenase
EC (curated) EC 1.1.1.85
Curated functionCatalyzes the oxidation of 3-carboxy-2-hydroxy-4-methylpentanoate (3-isopropylmalate) to 3-carboxy-4-methyl-2-oxopentanoate. The product decarboxylates to 4-methyl-2 oxopentanoate.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category C Energy production and conversion
E Amino acid transport and metabolism
Preferred nameleuB
eggNOG descriptionCatalyzes the oxidation of 3-carboxy-2-hydroxy-4- methylpentanoate (3-isopropylmalate) to 3-carboxy-4-methyl-2- oxopentanoate. The product decarboxylates to 4-methyl-2 oxopentanoate
Orthologous groupCOG0473
EC number EC 1.1.1.85
KEGG orthology K00052
KEGG pathways map00290, map00660, map01100, map01110, map01210, map01230
KEGG modules M00432, M00535
Gene Ontology (16) GO:0003674, GO:0003824, GO:0003862, GO:0005575, GO:0005622, GO:0005623, GO:0005737, GO:0008150, GO:0008152, GO:0016491, GO:0016614, GO:0016616 +4 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 0.06 · strong purifying
Polymorphic sites (≥ 0.1% of strains) 6 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
Iso_dhPF00180.26 8.9e-883–330 Isocitrate/isopropylmalate dehydrogenase

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

Closest characterised functional partner: leuC (3-isopropylmalate dehydratase large subunit), high confidence from genomic context alone (score 997 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2988c leuC 3-isopropylmalate dehydratase large subunit 999 997 ctx cooccurence:695 coexpression:857 database:900 textmining:702
Rv2987c leuD 3-isopropylmalate dehydratase small subunit 998 996 ctx cooccurence:713 coexpression:857 database:900 textmining:700
Rv3002c ilvN acetolactate synthase small subunit 995 985 coexpression:768 database:900 textmining:714
Rv2996c serA1 D-3-phosphoglycerate dehydrogenase 979 976 ctx neighborhood:869 coexpression:826
Rv3003c ilvB1 acetolactate synthase large subunit IlvB 977 970 ctx cooccurence:456 coexpression:409 database:900
Rv3470c ilvB2 acetolactate synthase large subunit 961 958 coexpression:402 database:900
Rv1820 ilvG acetolactate synthase large subunit IlvG 983 956 coexpression:407 database:900 textmining:629
Rv1559 ilvA threonine dehydratase IlvA 977 954 database:900 textmining:537
Rv3509c ilvX acetohydroxyacid synthase large subunit 960 948 coexpression:409 database:900
Rv3001c ilvC ketol-acid reductoisomerase 972 904 coexpression:837 textmining:725
Rv0189c ilvD dihydroxy-acid dehydratase 967 892 ctx cooccurence:435 coexpression:791 textmining:713
Rv3469c mhpE 4-hydroxy-2-oxovalerate aldolase MhpE 789 767 coexpression:694
Rv3710 leuA 2-isopropylmalate synthase 936 761 coexpression:696 textmining:745
Rv3534c hsaF 4-hydroxy-2-oxovalerate aldolase 763 738 coexpression:696
Rv1475c acn iron-regulated aconitate hydratase 798 737 database:446

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: 3-isopropylmalate dehydrogenase
  • MTBC0 PGAP product: 3-isopropylmalate dehydrogenase
  • Pfam (hmmscan --cut_ga): Iso_dh PF00180.26 (E=9e-88)
  • (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_217511.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Iso_dh (PF00180.26)
  • 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 COG0473
  • Curated reference: UniProt P9WKK9 (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 — 99 functional partner(s); context anchor leuC
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003182|Rv2995c|leuB
MKLAIIAGDGIGPEVTAEAVKVLDAVVPGVQKTSYDLGARRFHATGEVLPDSVVAELRNHDAILLGAIGDPSVPSGVLERGLLLRLRFELDHHINLRPARLYPGVASPLSGNPGIDFVVVREGTEGPYTGNGGAIRVGTPNEVATEVSVNTAFGVRRVVADAFERARRRRKHLTLVHKTNVLTFAGGLWLRTVDEVGECYPDVEVAYQHVDAATIHMITDPGRFDVIVTDNLFGDIITDLAAAVCGGIGLAASGNIDATRANPSMFEPVHGSAPDIAGQGIADPTAAIMSVALLLSHLGEHDAAARVDRAVEAHLATRGSERLATSDVGERIAAAL