KEGG   PATHWAY: tpr00020Help
tpr00020                    Pathway                                

Citrate cycle (TCA cycle) - Tsukamurella paurometabola
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].
Metabolism; Carbohydrate metabolism
BRITE hierarchy
Pathway map
tpr00020  Citrate cycle (TCA cycle)

Ortholog table
tpr_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:tpr00020]
tpr_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:tpr00020]
Other DBs
BSID: 151078
GO: 0006099
Tsukamurella paurometabola [GN:tpr]
Tpau_0848  Citrate (Si)-synthase [KO:K01647] [EC:]
Tpau_0855  citrate synthase I [KO:K01647] [EC:]
Tpau_1729  Citrate (Si)-synthase [KO:K01647] [EC:]
Tpau_1730  DNA binding domain protein, excisionase family [KO:K01647] [EC:]
Tpau_2075  aconitate hydratase 1 [KO:K01681] [EC:]
Tpau_2261  isocitrate dehydrogenase, NADP-dependent [KO:K00031] [EC:]
Tpau_1517  2-oxoglutarate dehydrogenase, E2 component, dihydrolipoamide succinyltransferase [KO:K00658] [EC:]
Tpau_0989  pyridine nucleotide-disulfide oxidoreductase dimerization region [KO:K00382] [EC:]
Tpau_3674  dihydrolipoamide dehydrogenase [KO:K00382] [EC:]
Tpau_2717  pyridine nucleotide-disulfide oxidoreductase dimerization region [KO:K00382] [EC:]
Tpau_3310  succinyl-CoA synthetase, alpha subunit [KO:K01902] [EC:]
Tpau_3311  succinyl-CoA synthetase, beta subunit [KO:K01903] [EC:]
Tpau_0965  succinate dehydrogenase or fumarate reductase, flavoprotein subunit [KO:K00239] [EC:]
Tpau_0964  succinate dehydrogenase and fumarate reductase iron-sulfur protein [KO:K00240] [EC:]
Tpau_0967  succinate dehydrogenase, cytochrome b556 subunit [KO:K00241]
Tpau_0966  succinate dehydrogenase cytochrome b subunit [KO:K00242]
Tpau_3124  hydro-lyase, Fe-S type, tartrate/fumarate subfamily, beta subunit [KO:K01676] [EC:]
Tpau_3120  fumarate lyase [KO:K01679] [EC:]
Tpau_1698  malate/quinone oxidoreductase [KO:K00116] [EC:]
Tpau_0937  pyruvate carboxylase [KO:K01958] [EC:]
Tpau_0372  Phosphoenolpyruvate carboxykinase (GTP) [KO:K01596] [EC:]
Tpau_2722  2-oxo-acid dehydrogenase E1 subunit, homodimeric type [KO:K00163] [EC:]
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
(map 2)
Nishizuka Y (ed).
[Metabolic Maps] (In Japanese)
Tokyo Kagaku Dojin (1980)
(map 3)
Nishizuka Y, Seyama Y, Ikai A, Ishimura Y, Kawaguchi A (eds).
[Cellular Functions and Metabolic Maps] (In Japanese)
Tokyo Kagaku Dojin (1997)
Michal G.
Biochemical Pathways
Wiley (1999)
KO pathway
LinkDB All DBs

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