KEGG   PATHWAY: psin00020
Entry
psin00020                   Pathway                                
Name
Citrate cycle (TCA cycle) - Pseudorhodoplanes sinuspersici
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
psin00020  Citrate cycle (TCA cycle)
psin00020

Module
psin_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:psin00020]
psin_M00009  Citrate cycle (TCA cycle, Krebs cycle) [PATH:psin00020]
psin_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:psin00020]
psin_M00011  Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:psin00020]
psin_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:psin00020]
Other DBs
GO: 0006099
Organism
Pseudorhodoplanes sinuspersici [GN:psin]
Gene
CAK95_07145  citryl-CoA lyase [KO:K01647] [EC:2.3.3.1]
CAK95_23010  citrate (Si)-synthase [KO:K01647] [EC:2.3.3.1]
CAK95_07545  aconitate hydratase 1 [KO:K01681] [EC:4.2.1.3]
CAK95_26515  isocitrate dehydrogenase (NADP(+)) [KO:K00031] [EC:1.1.1.42]
CAK95_26535  isocitrate dehydrogenase [KO:K00031] [EC:1.1.1.42]
CAK95_07460  2-oxoglutarate dehydrogenase E1 component [KO:K00164] [EC:1.2.4.2]
CAK95_07455  dihydrolipoamide succinyltransferase [KO:K00658] [EC:2.3.1.61]
CAK95_07450  dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
CAK95_23155  dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
CAK95_21470  ferredoxin oxidoreductase [KO:K00174] [EC:1.2.7.3 1.2.7.11]
CAK95_21465  2-oxoglutarate ferredoxin oxidoreductase subunit beta [KO:K00175] [EC:1.2.7.3 1.2.7.11]
CAK95_07465  succinate--CoA ligase subunit alpha [KO:K01902] [EC:6.2.1.5]
CAK95_09375  succinate--CoA ligase subunit alpha [KO:K01902] [EC:6.2.1.5]
CAK95_07475  succinate--CoA ligase subunit beta [KO:K01903] [EC:6.2.1.5]
CAK95_09380  succinate--CoA ligase [KO:K01903] [EC:6.2.1.5]
CAK95_07825  succinate dehydrogenase flavoprotein subunit [KO:K00239] [EC:1.3.5.1]
CAK95_26700  succinate dehydrogenase [KO:K00239] [EC:1.3.5.1]
CAK95_26695  hypothetical protein [KO:K00240] [EC:1.3.5.1]
CAK95_07835  succinate dehydrogenase iron-sulfur subunit [KO:K00240] [EC:1.3.5.1]
CAK95_07815  succinate dehydrogenase, cytochrome b556 subunit [KO:K00241]
CAK95_07820  succinate dehydrogenase, hydrophobic membrane anchor protein [KO:K00242]
CAK95_18400  fumarate hydratase [KO:K01676] [EC:4.2.1.2]
CAK95_14550  fumarate hydratase, class II [KO:K01679] [EC:4.2.1.2]
CAK95_07480  malate dehydrogenase [KO:K00024] [EC:1.1.1.37]
CAK95_06810  phosphoenolpyruvate carboxykinase (ATP) [KO:K01610] [EC:4.1.1.49]
CAK95_06945  transketolase [KO:K00163] [EC:1.2.4.1]
CAK95_23130  pyruvate dehydrogenase (acetyl-transferring) E1 component subunit alpha [KO:K00161] [EC:1.2.4.1]
CAK95_23135  pyruvate dehydrogenase complex E1 component subunit beta [KO:K00162] [EC:1.2.4.1]
CAK95_16815  pyruvate dehydrogenase complex dihydrolipoamide acetyltransferase [KO:K00627] [EC:2.3.1.12]
CAK95_23140  pyruvate dehydrogenase complex dihydrolipoamide acetyltransferase [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
psin00010  Glycolysis / Gluconeogenesis
psin00053  Ascorbate and aldarate metabolism
psin00061  Fatty acid biosynthesis
psin00071  Fatty acid degradation
psin00190  Oxidative phosphorylation
psin00220  Arginine biosynthesis
psin00250  Alanine, aspartate and glutamate metabolism
psin00280  Valine, leucine and isoleucine degradation
psin00350  Tyrosine metabolism
psin00470  D-Amino acid metabolism
psin00630  Glyoxylate and dicarboxylate metabolism
KO pathway
ko00020   
LinkDB

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