kstD Resolved · high auto-curated

H37Rv Rv3537 · MTBC0 mtbc0_003754 · 563 aa · 3999046–4000737 (+) · RefSeq NP_218054.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)3-oxosteroid 1-dehydrogenase
MTBC0 PGAP re-annotation3-oxosteroid 1-dehydrogenase
Revised (this work)3-oxosteroid 1-dehydrogenase. Pfam: FAD_binding_3 (PF01494.26), FAD_binding_2 (PF00890.31), FAD_oxidored (PF12831.14), DAO (PF01266.31), NAD_binding_8 (PF13450.13).

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

Curated reference (UniProt)

UniProt P71864 SwissProt · reviewed · Evidence at protein level
UniProt name3-oxosteroid 1-dehydrogenase
EC (curated) EC 1.3.99.4
Curated functionInvolved in the degradation of cholesterol. Catalyzes the elimination of the C-1 and C-2 hydrogen atoms of the A-ring from the polycyclic ring structure of 3-ketosteroids. Has a clear preference for 3-ketosteroids with a saturated A-ring, displaying highest activity on 5alpha-AD (5alpha-androstane-3,17-dione) and 5alpha-T (5alpha-testosterone, also known as 17beta-hydroxy-5alpha-androstane-3-one). Is also involved in the formation of 3-keto-1,4-diene-steroid from 3-keto-4-ene-steroid. Catalyzes the conversion of 3-oxo-23,24-bisnorchol-4-en-22-oyl-coenzyme A thioester (4-BNC-CoA) to 3-oxo-23,24.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category C Energy production and conversion
Preferred namekstD
eggNOG descriptionSuccinate dehydrogenase fumarate reductase flavoprotein subunit
Orthologous groupCOG1053
EC number EC 1.3.99.4
KEGG orthology K05898
KEGG pathways map00984, map01100, map01120
Gene Ontology (42) GO:0003674, GO:0003824, GO:0005575, GO:0005623, GO:0005886, GO:0006066, GO:0006629, GO:0006694, GO:0006706, GO:0006707, GO:0008150, GO:0008152 +30 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 0.417 · 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
FAD_binding_3PF01494.26 1.4e-056–93 FAD binding domain
FAD_binding_2PF00890.31 1.6e-867–541 FAD binding domain
FAD_oxidoredPF12831.14 4.6e-117–82 FAD dependent oxidoreductase
DAOPF01266.31 7.8e-097–52 FAD dependent oxidoreductase
NAD_binding_8PF13450.13 4.6e-0610–45 NAD(P)-binding Rossmann-like domain

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

Closest characterised functional partner: Rv3538 (dehydrogenase), high confidence from genomic context alone (score 981 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3538 dehydrogenase 980 981 ctx neighborhood:882 coexpression:818
Rv3526 kshA 3-ketosteroid-9-alpha-monooxygenase oxygenase subunit 998 978 ctx cooccurence:753 database:900 textmining:932
Rv3316 sdhC succinate dehydrogenase cytochrome B-556 subunit 962 959 coexpression:650 experimental:707 database:621
Rv0760c hyp hypothetical protein 940 938 ctx cooccurence:404 database:900
Rv3571 kshB 3-ketosteroid-9-alpha-hydroxylase reductase subunit 992 936 database:900 textmining:895
Rv1817 flavoprotein 947 935 database:900
Rv1248c kgd multifunctional 2-oxoglutarate dehydrogenase E1 component /2-oxoglutarate dehydrogenase dihydrolipoyllysine-residue succinyltransferase 937 918 coexpression:894
Rv3319 sdhB succinate dehydrogenase iron-sulphur protein subunit 881 875 coexpression:484 experimental:454 database:578
Rv0247c succinate dehydrogenase iron-sulfur subunit 881 875 coexpression:484 experimental:454 database:578
Rv1553 frdB fumarate reductase iron-sulfur subunit 881 875 coexpression:487 experimental:454 database:578
Rv3568c hsaC extradiol dioxygenase 955 867 ctx cooccurence:765 textmining:678
Rv3540c ltp2 lipid transfer protein 848 815 ctx cooccurence:546 database:500
Rv3534c hsaF 4-hydroxy-2-oxovalerate aldolase 929 808 ctx neighborhood:607 coexpression:443 textmining:648
Rv3535c hsaG acetaldehyde dehydrogenase 892 808 ctx neighborhood:673 textmining:465
Rv3317 sdhD succinate dehydrogenase hydrophobic membrane anchor subunit 812 797 coexpression:647 experimental:430

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-oxosteroid 1-dehydrogenase
  • MTBC0 PGAP product: 3-oxosteroid 1-dehydrogenase
  • Pfam (hmmscan --cut_ga): FAD_binding_3 PF01494.26 (E=1e-05), FAD_binding_2 PF00890.31 (E=2e-86), FAD_oxidored PF12831.14 (E=5e-11), DAO PF01266.31 (E=8e-09), NAD_binding_8 PF13450.13 (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_218054.1)
  • Domains: Pfam-A via hmmscan --cut_ga — FAD_binding_3 (PF01494.26), FAD_binding_2 (PF00890.31), FAD_oxidored (PF12831.14), DAO (PF01266.31), NAD_binding_8 (PF13450.13)
  • 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 COG1053
  • Curated reference: UniProt P71864 (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 — 110 functional partner(s); context anchor Rv3538
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003754|Rv3537|kstD
MTVQEFDVVVVGSGAAGMVAALVAAHRGLSTVVVEKAPHYGGSTARSGGGVWIPNNEVLKRRGVRDTPEAARTYLHGIVGEIVEPERIDAYLDRGPEMLSFVLKHTPLKMCWVPGYSDYYPEAPGGRPGGRSIEPKPFNARKLGADMAGLEPAYGKVPLNVVVMQQDYVRLNQLKRHPRGVLRSMKVGARTMWAKATGKNLVGMGRALIGPLRIGLQRAGVPVELNTAFTDLFVENGVVSGVYVRDSHEAESAEPQLIRARRGVILACGGFEHNEQMRIKYQRAPITTEWTVGASANTGDGILAAEKLGAALDLMDDAWWGPTVPLVGKPWFALSERNSPGSIIVNMSGKRFMNESMPYVEACHHMYGGEHGQGPGPGENIPAWLVFDQRYRDRYIFAGLQPGQRIPSRWLDSGVIVQADTLAELAGKAGLPADELTATVQRFNAFARSGVDEDYHRGESAYDRYYGDPSNKPNPNLGEVGHPPYYGAKMVPGDLGTKGGIRTDVNGRALRDDGSIIDGLYAAGNVSAPVMGHTYPGPGGTIGPAMTFGYLAALHIADQAGKR