Rv2455c Family assigned · medium auto-curated

H37Rv Rv2455c · MTBC0 mtbc0_002614 · 653 aa · 2778991–2780952 (-) · RefSeq NP_216971.1

Annotation: from legacy to revised

Legacy (H37Rv / Mycobrowser)2-oxoglutarate oxidoreductase subunit KorA
MTBC0 PGAP re-annotation2-oxoacid:acceptor oxidoreductase subunit alpha
Revised (this work)2-oxoacid:acceptor oxidoreductase subunit alpha. Pfam: POR (PF01558.26), POR_N (PF01855.25), PFOR_II (PF17147.10).

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

Curated reference (UniProt)

UniProt O53182 SwissProt · reviewed · Evidence at protein level
UniProt name2-oxoglutarate oxidoreductase subunit KorA
EC (curated) EC 1.2.7.3
Curated functionComponent of KG oxidoreductase (KOR) that catalyzes the CoA-dependent oxidative decarboxylation of 2-oxoglutarate (alpha-ketoglutarate, KG) to succinyl-CoA. Methyl viologen can act as electron acceptor in vitro; the physiologic electron acceptor is unknown. Is involved in the alternative TCA pathway that functions concurrently with fatty acid beta-oxidation. Since a growing body of evidence indicates that lipids (for example cholesterol and fatty acids) are a predominant growth substrate for M.tuberculosis during infection, flux through KOR likely represents an important step in intermediary m.

Functional vocabulary (eggNOG-mapper, orthology transfer)

COG category C Energy production and conversion
Preferred namekorA
eggNOG descriptionferredoxin oxidoreductase
Orthologous groupCOG0674
EC number EC 1.2.7.11, EC 1.2.7.3
KEGG orthology K00174
KEGG pathways map00010, map00020, map00620, map00650, map00720, map01100, map01120, map01130, map01200
KEGG modules M00009, M00011, M00173, M00620
Gene Ontology (17) GO:0003674, GO:0003824, GO:0005575, GO:0005618, GO:0005623, GO:0005886, GO:0006950, GO:0006979, GO:0008150, GO:0008152, GO:0016020, GO:0016491 +5 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 0.465 · purifying
Polymorphic sites (≥ 0.1% of strains) 6 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
PORPF01558.26 1.7e-2231–228 Pyruvate ferredoxin/flavodoxin oxidoreductase
POR_NPF01855.25 1.9e-59269–486 Pyruvate flavodoxin/ferredoxin oxidoreductase, thiamine diP-bdg
PFOR_IIPF17147.10 2.2e-07526–612 Pyruvate:ferredoxin oxidoreductase core domain II

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

Closest characterised functional partner: korB (2-oxoglutarate oxidoreductase subunit KorB), high confidence from genomic context alone (score 1000 excluding text-mining).

PartnerProductScoreNo text-miningChannels (≥400)
Rv2454c korB 2-oxoglutarate oxidoreductase subunit KorB 999 1000 ctx neighborhood:881 cooccurence:774 coexpression:989 experimental:999 database:900 textmining:932
Rv0066c icd2 isocitrate dehydrogenase 987 975 coexpression:668 database:900 textmining:516
Rv2540c aroF chorismate synthase 968 967 experimental:965
Rv0408 pta phosphate acetyltransferase 987 953 ctx neighborhood:544 database:900 textmining:745
Rv0952 sucD succinyl-CoA ligase subunit alpha 979 948 database:900 textmining:628
Rv0951 sucC succinyl-CoA ligase subunit beta 979 946 database:900 textmining:631
Rv0211 pckA phosphoenolpyruvate carboxykinase 959 944 coexpression:730 database:800
Rv3153 nuoI NADH-quinone oxidoreductase subunit I 971 942 coexpression:415 experimental:852 textmining:527
Rv3667 acs acetyl-CoAsynthetase 964 929 database:900 textmining:516
Rv3002c ilvN acetolactate synthase small subunit 929 921 database:900
Rv1617 pykA pyruvate kinase 967 920 database:900 textmining:617
Rv3285 accA3 bifunctional protein acetyl-/propionyl-CoA carboxylase subunit alpha AccA 940 919 database:900
Rv2501c accA1 acetyl/propionyl-CoA carboxylase subuit alpha 939 918 database:900
Rv3509c ilvX acetohydroxyacid synthase large subunit 935 915 database:900
Rv1820 ilvG acetolactate synthase large subunit IlvG 935 914 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: 2-oxoglutarate oxidoreductase subunit KorA
  • MTBC0 PGAP product: 2-oxoacid:acceptor oxidoreductase subunit alpha
  • Pfam (hmmscan --cut_ga): POR PF01558.26 (E=2e-22), POR_N PF01855.25 (E=2e-59), PFOR_II PF17147.10 (E=2e-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_216971.1)
  • Domains: Pfam-A via hmmscan --cut_ga — POR (PF01558.26), POR_N (PF01855.25), PFOR_II (PF17147.10)
  • 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 COG0674
  • Curated reference: UniProt O53182 (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 — 181 functional partner(s); context anchor korB
  • Primary literature: none located yet; annotation rests on the domain/homology sources above.

Ancestral MTBC0 protein sequence

>mtbc0_002614|Rv2455c|
MDPNGSGAGPESHDAAFHAAPDRQRLENVVIRFAGDSGDGMQLTGDRFTSEAALFGNDLATQPNYPAEIRAPAGTLPGVSSFQIQIADYDILTAGDRPDVLVAMNPAALKANIGDLPLGGMVIVNSDEFTKRNLTKVGYVTNPLESGELSDYVVHTVAMTTLTLGAVEAIGASKKDGQRAKNMFALGLLSWMYGRELEHSEAFIREKFARKPEIAEANVLALKAGWNYGETTEAFGTTYEIPPATLPPGEYRQISGNTALAYGIVVAGQLAGLPVVLGSYPITPASDILHELSKHKNFNVVTFQAEDEIGGICAALGAAYGGALGVTSTSGPGISLKSEALGLGVMTELPLLVIDVQRGGPSTGLPTKTEQADLLQALYGRNGESPVAVLAPRSPADCFETALEAVRIAVSYHTPVILLSDGAIANGSEPWRIPDVNALPPIKHTFAKPGEPFQPYARDRETLARQFAIPGTPGLEHRIGGLEAANGSGDISYEPTNHDLMVRLRQAKIDGIHVPDLEVDDPTGDAELLLIGWGSSYGPIGEACRRARRRGTKVAHAHLRYLNPFPANLGEVLRRYPKVVAPELNLGQLAQVLRGKYLVDVQSVTKVKGVSFLADEIGRFIRAALAGRLAELEQDKTLVARLSAATAGAGANG