sdhB Family assigned · medium auto-curated

H37Rv Rv3319 · MTBC0 mtbc0_003529 · 263 aa · 3728910–3729701 (+) · RefSeq NP_217836.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)succinate dehydrogenase iron-sulphur protein subunit
MTBC0 PGAP re-annotationsuccinate dehydrogenase iron-sulfur subunit
Revised (this work)Succinate dehydrogenase iron-sulfur subunit. Pfam: Fer2_3 (PF13085.12), Fer4_10 (PF13237.12), Fer4_8 (PF13183.12), Fer4_17 (PF13534.12).

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

Curated reference (UniProt)

UniProt O53371 TrEMBL · unreviewed · Evidence at protein level
UniProt namesuccinate dehydrogenase
EC (curated) EC 1.3.5.1

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category C Energy production and conversion
Preferred namesdhB
eggNOG descriptionsuccinate dehydrogenase
Orthologous groupCOG0479
EC number EC 1.3.5.1, EC 1.3.5.4
KEGG orthology K00240, K00245
KEGG pathways map00020, map00190, map00620, map00650, map00720, map01100, map01110, map01120, map01130, map01200, map02020
KEGG modules M00009, M00011, M00149, M00150, M00173, M00374, M00376

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 0.318 · 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
Fer2_3PF13085.12 4.1e-2925–139 2Fe-2S iron-sulfur cluster binding domain
Fer4_10PF13237.12 3.0e-10170–243 4Fe-4S dicluster domain
Fer4_8PF13183.12 2.3e-10174–246 4Fe-4S dicluster domain
Fer4_17PF13534.12 7.8e-07175–246 4Fe-4S dicluster domain

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

Closest characterised functional partner: sdhD (succinate dehydrogenase hydrophobic membrane anchor subunit), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv3317 sdhD succinate dehydrogenase hydrophobic membrane anchor subunit 999 1000 ctx neighborhood:758 cooccurence:760 coexpression:673 experimental:997 database:900 textmining:837
Rv3318 sdhA succinate dehydrogenase flavoprotein subunit 999 1000 ctx neighborhood:881 cooccurence:774 coexpression:570 experimental:997 database:956 textmining:901
Rv3316 sdhC succinate dehydrogenase cytochrome B-556 subunit 999 1000 ctx neighborhood:758 cooccurence:766 coexpression:698 experimental:997 database:962 textmining:909
Rv1552 frdA fumarate reductase flavoprotein subunit 997 997 ctx cooccurence:766 coexpression:484 experimental:454 database:956
Rv0248c succinate dehydrogenase flavoprotein subunit 997 993 ctx cooccurence:446 coexpression:489 experimental:454 database:956 textmining:628
Rv0951 sucC succinyl-CoA ligase subunit beta 987 979 coexpression:646 database:900 textmining:428
Rv0952 sucD succinyl-CoA ligase subunit alpha 985 979 coexpression:651 database:900
Rv1554 frdC fumarate reductase membrane anchor subunit 981 974 coexpression:452 experimental:549 database:900
Rv1555 frdD fumarate reductase membrane anchor subunit 980 973 coexpression:419 experimental:549 database:900
Rv1248c kgd multifunctional 2-oxoglutarate dehydrogenase E1 component /2-oxoglutarate dehydrogenase dihydrolipoyllysine-residue succinyltransferase 967 951 coexpression:932
Rv1098c fum fumarate hydratase 954 949 coexpression:423 database:900
Rv1731 gabD2 succinate-semialdehyde dehydrogenase 917 912 database:900
Rv1553 frdB fumarate reductase iron-sulfur subunit 915 912 database:900
Rv0234c gabD1 succinate-semialdehyde dehydrogenase 915 912 database:900
Rv0247c succinate dehydrogenase iron-sulfur subunit 929 909 database:900

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: succinate dehydrogenase iron-sulphur protein subunit
  • MTBC0 PGAP product: succinate dehydrogenase iron-sulfur subunit
  • Pfam (hmmscan --cut_ga): Fer2_3 PF13085.12 (E=4e-29), Fer4_10 PF13237.12 (E=3e-10), Fer4_8 PF13183.12 (E=2e-10), Fer4_17 PF13534.12 (E=8e-07)
  • (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_217836.1)
  • Domains: Pfam-A via hmmscan --cut_ga — Fer2_3 (PF13085.12), Fer4_10 (PF13237.12), Fer4_8 (PF13183.12), Fer4_17 (PF13534.12)
  • 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 COG0479
  • Curated reference: UniProt O53371 (TrEMBL, unreviewed; 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 — 105 functional partner(s); context anchor sdhD
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_003529|Rv3319|sdhB
MSVEPDVETLDPPLPPVPDGAVMVTVKIARFNPDDPDAFAATGGWQSFRVPCLPSDRLLNLLIYIKGYLDGTLTFRRSCAHGVCGSDAMRINGVNRLACKVLMRDLLPKKKGKSLTVTVEPIRGLPVEKDLVVDMEPFFDAYRAIKPYLITSGNPPTRERIQSPTDRARYDDTTKCILCACCTTSCPVFWHEGSYFGPAAIVNAHRFIFDSRDEAAAERLDILNEVDGVWRCRTTFNCTESCPRGIEVTKAIQEVKRALMFTR