ilvD Resolved · high auto-curated

H37Rv Rv0189c · MTBC0 mtbc0_000203 · 575 aa · 220344–222071 (-) · RefSeq NP_214703.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)dihydroxy-acid dehydratase
MTBC0 PGAP re-annotationdihydroxy-acid dehydratase
Revised (this work)Dihydroxy-acid dehydratase. Pfam: ILVD_EDD_N (PF00920.28), ILV_EDD_C (PF24877.2).

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

Curated reference (UniProt)

UniProt P9WKJ5 SwissProt · reviewed · Evidence at protein level
UniProt nameDihydroxy-acid dehydratase
EC (curated) EC 4.2.1.9
Curated functionFunctions in the biosynthesis of branched-chain amino acids. Catalyzes the dehydration of (2R,3R)-2,3-dihydroxy-3-methylpentanoate (2,3-dihydroxy-3-methylvalerate) into 2-oxo-3-methylpentanoate (2-oxo-3-methylvalerate) and of (2R)-2,3-dihydroxy-3-methylbutanoate (2,3-dihydroxyisovalerate) into 2-oxo-3-methylbutanoate (2-oxoisovalerate), the penultimate precursor to L-isoleucine and L-valine, respectively. Is specific for the (R) isomer of 2,3-dihydroxy-3-methylbutanoate, with no catalytic activity against the (S) isomer.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category E Amino acid transport and metabolism
Preferred nameilvD
eggNOG descriptionBelongs to the ILVD EDD family
Orthologous groupCOG0129
EC number EC 4.2.1.9
KEGG orthology K01687
KEGG pathways map00290, map00770, map01100, map01110, map01130, map01210, map01230
KEGG modules M00019, M00570
Gene Ontology (36) GO:0003674, GO:0003824, GO:0004160, GO:0005575, GO:0005623, GO:0005886, GO:0006082, GO:0006520, GO:0006807, GO:0008150, GO:0008152, GO:0008652 +24 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 0.713 · relaxed/neutral
Polymorphic sites (≥ 0.1% of strains) 4 synonymous, 8 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
ILVD_EDD_NPF00920.28 4.1e-13249–371 Dihydroxy-acid/6-phosphogluconate dehydratase N-terminal
ILV_EDD_CPF24877.2 1.3e-68383–572 Dihydroxy-acid/6-phosphogluconate dehydratase C-terminal

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

Closest characterised functional partner: ilvC (ketol-acid reductoisomerase), high confidence from genomic context alone (score 995 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3001c ilvC ketol-acid reductoisomerase 998 995 ctx cooccurence:733 coexpression:791 database:900 textmining:802
Rv2210c ilvE branched-chain amino acid aminotransferase 994 982 coexpression:669 database:900 textmining:736
Rv3710 leuA 2-isopropylmalate synthase 988 965 coexpression:655 database:900 textmining:695
Rv3003c ilvB1 acetolactate synthase large subunit IlvB 967 955 ctx fusion:615 cooccurence:753 coexpression:506
Rv2988c leuC 3-isopropylmalate dehydratase large subunit 967 933 ctx cooccurence:546 coexpression:846 textmining:540
Rv0337c aspC aspartate aminotransferase 927 921 database:900
Rv2225 panB 3-methyl-2-oxobutanoate hydroxymethyltransferase 929 901 database:900
Rv2987c leuD 3-isopropylmalate dehydratase small subunit 936 893 ctx cooccurence:606 coexpression:718 textmining:427
Rv2995c leuB 3-isopropylmalate dehydrogenase 967 892 ctx cooccurence:435 coexpression:791 textmining:713
Rv3002c ilvN acetolactate synthase small subunit 960 892 ctx cooccurence:583 coexpression:650 textmining:655
Rv3470c ilvB2 acetolactate synthase large subunit 869 856 ctx cooccurence:715 coexpression:499
Rv1559 ilvA threonine dehydratase IlvA 946 845 ctx cooccurence:405 coexpression:729 textmining:667
Rv3859c gltB glutamate synthase large subunit 933 798 coexpression:771 textmining:682
Rv0812 4-amino-4-deoxychorismate lyase 815 791 coexpression:668
Rv0190 ricR hyp hypothetical protein 773 773 ctx neighborhood:772

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: dihydroxy-acid dehydratase
  • MTBC0 PGAP product: dihydroxy-acid dehydratase
  • Pfam (hmmscan --cut_ga): ILVD_EDD_N PF00920.28 (E=4e-132), ILV_EDD_C PF24877.2 (E=1e-68)
  • (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_214703.1)
  • Domains: Pfam-A via hmmscan --cut_ga — ILVD_EDD_N (PF00920.28), ILV_EDD_C (PF24877.2)
  • 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 COG0129
  • Curated reference: UniProt P9WKJ5 (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 — 88 functional partner(s); context anchor ilvC
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_000203|Rv0189c|ilvD
MPQTTDEAASVSTVADIKPRSRDVTDGLEKAAARGMLRAVGMDDEDFAKPQIGVASSWNEITPCNLSLDRLANAVKEGVFSAGGYPLEFGTISVSDGISMGHEGMHFSLVSREVIADSVEVVMQAERLDGSVLLAGCDKSLPGMLMAAARLDLAAVFLYAGSILPGRAKLSDGSERDVTIIDAFEAVGACSRGLMSRADVDAIERAICPGEGACGGMYTANTMASAAEALGMSLPGSAAPPATDRRRDGFARRSGQAVVELLRRGITARDILTKEAFENAIAVVMAFGGSTNAVLHLLAIAHEANVALSLQDFSRIGSGVPHLADVKPFGRHVMSDVDHIGGVPVVMKALLDAGLLHGDCLTVTGHTMAENLAAITPPDPDGKVLRALANPIHPSGGITILHGSLAPEGAVVKTAGFDSDVFEGTARVFDGERAALDALEDGTITVGDAVVIRYEGPKGGPGMREMLAITGAIKGAGLGKDVLLLTDGRFSGGTTGLCVGHIAPEAVDGGPIALLRNGDRIRLDVAGRVLDVLADPAEFASRQQDFSPPPPRYTTGVLSKYVKLVSSAAVGAVCG