KEGG   PATHWAY: efo00020
Entry
efo00020                    Pathway                                
Name
Citrate cycle (TCA cycle) - Epinephelus fuscoguttatus (brown-marbled grouper)
Description
The citrate cycle (TCA cycle, Krebs cycle) is an important aerobic pathway for the final steps of the oxidation of carbohydrates and fatty acids. The cycle starts with acetyl-CoA, the activated form of acetate, derived from glycolysis and pyruvate oxidation for carbohydrates and from beta oxidation of fatty acids. The two-carbon acetyl group in acetyl-CoA is transferred to the four-carbon compound of oxaloacetate to form the six-carbon compound of citrate. In a series of reactions two carbons in citrate are oxidized to CO2 and the reaction pathway supplies NADH for use in the oxidative phosphorylation and other metabolic processes. The pathway also supplies important precursor metabolites including 2-oxoglutarate. At the end of the cycle the remaining four-carbon part is transformed back to oxaloacetate. According to the genome sequence data, many organisms seem to lack genes for the full cycle [MD:M00009], but contain genes for specific segments [MD:M00010 M00011].
Class
Metabolism; Carbohydrate metabolism
Pathway map
efo00020  Citrate cycle (TCA cycle)
efo00020

Module
efo_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:efo00020]
efo_M00009  Citrate cycle (TCA cycle, Krebs cycle) [PATH:efo00020]
efo_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:efo00020]
efo_M00011  Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:efo00020]
efo_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:efo00020]
Other DBs
GO: 0006099
Organism
Epinephelus fuscoguttatus (brown-marbled grouper) [GN:efo]
Gene
125891368  cs; citrate synthase, mitochondrial [KO:K01647] [EC:2.3.3.1]
125879673  aclya; ATP-citrate synthase [KO:K01648] [EC:2.3.3.8]
125880863  ATP-citrate synthase-like isoform X1 [KO:K01648] [EC:2.3.3.8]
125884062  aco1; cytoplasmic aconitate hydratase [KO:K01681] [EC:4.2.1.3]
125878932  aconitate hydratase, mitochondrial-like [KO:K01681] [EC:4.2.1.3]
125880335  aco2; aconitate hydratase, mitochondrial [KO:K01681] [EC:4.2.1.3]
125899569  idh1; isocitrate dehydrogenase [NADP] cytoplasmic [KO:K00031] [EC:1.1.1.42]
125880105  isocitrate dehydrogenase [NADP], mitochondrial-like [KO:K00031] [EC:1.1.1.42]
125887238  idh2; isocitrate dehydrogenase [NADP], mitochondrial [KO:K00031] [EC:1.1.1.42]
125891178  isocitrate dehydrogenase [NAD] subunit gamma, mitochondrial-like [KO:K00030] [EC:1.1.1.41]
125891343  idh3g; isocitrate dehydrogenase [NAD] subunit gamma, mitochondrial isoform X1 [KO:K00030] [EC:1.1.1.41]
125887397  idh3a; isocitrate dehydrogenase [NAD] subunit alpha, mitochondrial isoform X1 [KO:K00030] [EC:1.1.1.41]
125900136  isocitrate dehydrogenase [NAD] subunit alpha, mitochondrial-like isoform X1 [KO:K00030] [EC:1.1.1.41]
125887668  idh3b; isocitrate dehydrogenase [NAD] subunit beta, mitochondrial isoform X1 [KO:K00030] [EC:1.1.1.41]
125889749  ogdha; oxoglutarate (alpha-ketoglutarate) dehydrogenase a (lipoamide) isoform X1 [KO:K00164] [EC:1.2.4.2]
125903172  ogdhl; 2-oxoglutarate dehydrogenase-like, mitochondrial [KO:K00164] [EC:1.2.4.2]
125905709  ogdhb; 2-oxoglutarate dehydrogenase complex component E1 [KO:K00164] [EC:1.2.4.2]
125897159  dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial-like [KO:K00658] [EC:2.3.1.61]
125900520  dlst; dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial [KO:K00658] [EC:2.3.1.61]
125887801  dldh; dihydrolipoyl dehydrogenase, mitochondrial [KO:K00382] [EC:1.8.1.4]
125885938  suclg1; succinate--CoA ligase [ADP/GDP-forming] subunit alpha, mitochondrial [KO:K01899] [EC:6.2.1.4 6.2.1.5]
125897441  suclg2; succinyl-CoA ligase [GDP-forming] subunit beta, mitochondrial [KO:K01900] [EC:6.2.1.4 6.2.1.5]
125899973  sucla2; succinate--CoA ligase [ADP-forming] subunit beta, mitochondrial [KO:K01900] [EC:6.2.1.4 6.2.1.5]
125893053  sdha; succinate dehydrogenase [ubiquinone] flavoprotein subunit, mitochondrial [KO:K00234] [EC:1.3.5.1]
125892246  succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial-like [KO:K00235] [EC:1.3.5.1]
125892270  sdhb; succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial [KO:K00235] [EC:1.3.5.1]
125901989  sdhc; succinate dehydrogenase cytochrome b560 subunit, mitochondrial [KO:K00236]
125888269  succinate dehydrogenase [ubiquinone] cytochrome b small subunit B, mitochondrial-like [KO:K00237]
125895456  fh; fumarate hydratase, mitochondrial [KO:K01679] [EC:4.2.1.2]
125903213  mdh1ab; malate dehydrogenase 1Ab, NAD (soluble) [KO:K00025] [EC:1.1.1.37]
125886379  malate dehydrogenase, cytoplasmic-like [KO:K00025] [EC:1.1.1.37]
125892830  mdh2; malate dehydrogenase, mitochondrial [KO:K00026] [EC:1.1.1.37]
125883324  pcxb; pyruvate carboxylase, mitochondrial [KO:K01958] [EC:6.4.1.1]
125882212  pck2; phosphoenolpyruvate carboxykinase [GTP], mitochondrial [KO:K01596] [EC:4.1.1.32]
125896920  pck1; phosphoenolpyruvate carboxykinase, cytosolic [GTP] [KO:K01596] [EC:4.1.1.32]
125882239  pdha1b; pyruvate dehydrogenase E1 subunit alpha 1b isoform X1 [KO:K00161] [EC:1.2.4.1]
125898304  pdha1a; pyruvate dehydrogenase E1 subunit alpha 1a [KO:K00161] [EC:1.2.4.1]
125888300  pyruvate dehydrogenase E1 component subunit alpha, somatic form, mitochondrial-like isoform X1 [KO:K00161] [EC:1.2.4.1]
125893158  pdhb; pyruvate dehydrogenase E1 component subunit beta, mitochondrial [KO:K00162] [EC:1.2.4.1]
125898400  dlat; dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex, mitochondrial [KO:K00627] [EC:2.3.1.12]
Compound
C00022  Pyruvate
C00024  Acetyl-CoA
C00026  2-Oxoglutarate
C00036  Oxaloacetate
C00042  Succinate
C00068  Thiamin diphosphate
C00074  Phosphoenolpyruvate
C00091  Succinyl-CoA
C00122  Fumarate
C00149  (S)-Malate
C00158  Citrate
C00311  Isocitrate
C00417  cis-Aconitate
C05125  2-(alpha-Hydroxyethyl)thiamine diphosphate
C05379  Oxalosuccinate
C05381  3-Carboxy-1-hydroxypropyl-ThPP
C15972  Enzyme N6-(lipoyl)lysine
C15973  Enzyme N6-(dihydrolipoyl)lysine
C16254  [Dihydrolipoyllysine-residue succinyltransferase] S-succinyldihydrolipoyllysine
C16255  [Dihydrolipoyllysine-residue acetyltransferase] S-acetyldihydrolipoyllysine
Reference
  Authors
Nishizuka Y (ed).
  Title
[Metabolic Maps] (In Japanese)
  Journal
Tokyo Kagaku Dojin (1980)
Reference
  Authors
Nishizuka Y, Seyama Y, Ikai A, Ishimura Y, Kawaguchi A (eds).
  Title
[Cellular Functions and Metabolic Maps] (In Japanese)
  Journal
Tokyo Kagaku Dojin (1997)
Reference
  Authors
Michal G.
  Title
Biochemical Pathways
  Journal
Wiley (1999)
Related
pathway
efo00010  Glycolysis / Gluconeogenesis
efo00053  Ascorbate and aldarate metabolism
efo00061  Fatty acid biosynthesis
efo00062  Fatty acid elongation
efo00071  Fatty acid degradation
efo00190  Oxidative phosphorylation
efo00220  Arginine biosynthesis
efo00250  Alanine, aspartate and glutamate metabolism
efo00280  Valine, leucine and isoleucine degradation
efo00350  Tyrosine metabolism
efo00470  D-Amino acid metabolism
efo00630  Glyoxylate and dicarboxylate metabolism
KO pathway
ko00020   
LinkDB

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