KEGG   PATHWAY: chel00020
Entry
chel00020                   Pathway                                
Name
Citrate cycle (TCA cycle) - Chelatococcus sp. CO-6
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
chel00020  Citrate cycle (TCA cycle)
chel00020

Module
chel_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:chel00020]
chel_M00009  Citrate cycle (TCA cycle, Krebs cycle) [PATH:chel00020]
chel_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:chel00020]
chel_M00011  Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:chel00020]
chel_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:chel00020]
Other DBs
GO: 0006099
Organism
Chelatococcus sp. CO-6 [GN:chel]
Gene
AL346_01145  [KO:K00031] [EC:1.1.1.42]
AL346_01700  [KO:K01679] [EC:4.2.1.2]
AL346_02130  [KO:K00382] [EC:1.8.1.4]
AL346_03625  [KO:K01676] [EC:4.2.1.2]
AL346_07905  [KO:K01610] [EC:4.1.1.49]
AL346_08835  [KO:K00382] [EC:1.8.1.4]
AL346_08840  [KO:K00658] [EC:2.3.1.61]
AL346_08845  sucA; 2-oxoglutarate dehydrogenase [KO:K00164] [EC:1.2.4.2]
AL346_08850  [KO:K01902] [EC:6.2.1.5]
AL346_08855  sucC; succinyl-CoA synthetase subunit beta [KO:K01903] [EC:6.2.1.5]
AL346_08860  [KO:K00024] [EC:1.1.1.37]
AL346_08890  [KO:K00240] [EC:1.3.5.1]
AL346_08895  [KO:K00239] [EC:1.3.5.1]
AL346_08900  [KO:K00242]
AL346_08905  [KO:K00241]
AL346_09205  [KO:K27802]
AL346_11400  [KO:K00627] [EC:2.3.1.12]
AL346_12015  [KO:K00163] [EC:1.2.4.1]
AL346_14810  [KO:K01958] [EC:6.4.1.1]
AL346_17795  gltA; type II citrate synthase [KO:K01647] [EC:2.3.3.1]
AL346_17910  [KO:K00161] [EC:1.2.4.1]
AL346_17915  [KO:K00162] [EC:1.2.4.1]
AL346_17920  [KO:K00627] [EC:2.3.1.12]
AL346_17925  [KO:K00382] [EC:1.8.1.4]
AL346_20535  [KO:K01647] [EC:2.3.3.1]
AL346_22565  [KO:K00627] [EC:2.3.1.12]
AL346_24425  [KO:K01647] [EC:2.3.3.1]
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
chel00010  Glycolysis / Gluconeogenesis
chel00053  Ascorbate and aldarate metabolism
chel00061  Fatty acid biosynthesis
chel00071  Fatty acid degradation
chel00190  Oxidative phosphorylation
chel00220  Arginine biosynthesis
chel00250  Alanine, aspartate and glutamate metabolism
chel00280  Valine, leucine and isoleucine degradation
chel00350  Tyrosine metabolism
chel00470  D-Amino acid metabolism
chel00630  Glyoxylate and dicarboxylate metabolism
KO pathway
ko00020   

DBGET integrated database retrieval system