KEGG   PATHWAY: fpal00020
Entry
fpal00020                   Pathway                                
Name
Citrate cycle (TCA cycle) - Flavobacterium pallidum
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
fpal00020  Citrate cycle (TCA cycle)
fpal00020

Module
fpal_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:fpal00020]
fpal_M00009  Citrate cycle (TCA cycle, Krebs cycle) [PATH:fpal00020]
fpal_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:fpal00020]
fpal_M00011  Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:fpal00020]
fpal_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:fpal00020]
Other DBs
GO: 0006099
Organism
Flavobacterium pallidum [GN:fpal]
Gene
HYN49_00455  gltA; citrate (Si)-synthase [KO:K01647] [EC:2.3.3.1]
HYN49_00090  aconitate hydratase [KO:K01681] [EC:4.2.1.3]
HYN49_09680  NADP-dependent isocitrate dehydrogenase [KO:K00031] [EC:1.1.1.42]
HYN49_02365  2-oxoglutarate dehydrogenase E1 component [KO:K00164] [EC:1.2.4.2]
HYN49_00805  2-oxoglutarate dehydrogenase [KO:K00658] [EC:2.3.1.61]
HYN49_02360  dihydrolipoyllysine-residue succinyltransferase [KO:K00658] [EC:2.3.1.61]
HYN49_08375  diapophytoene dehydrogenase [KO:K00658] [EC:2.3.1.61]
HYN49_12040  lpdA; dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
HYN49_12280  lpdA; dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
HYN49_11780  succinate--CoA ligase subunit alpha [KO:K01902] [EC:6.2.1.5]
HYN49_09620  ADP-forming succinate--CoA ligase subunit beta [KO:K01903] [EC:6.2.1.5]
HYN49_04265  fumarate reductase/succinate dehydrogenase flavoprotein subunit [KO:K00239] [EC:1.3.5.1]
HYN49_04260  succinate dehydrogenase/fumarate reductase iron-sulfur subunit [KO:K00240] [EC:1.3.5.1]
HYN49_04270  succinate dehydrogenase [KO:K00241]
HYN49_11575  fumC; class II fumarate hydratase [KO:K01679] [EC:4.2.1.2]
HYN49_14425  malate dehydrogenase [KO:K00024] [EC:1.1.1.37]
HYN49_02305  pckA; phosphoenolpyruvate carboxykinase (ATP) [KO:K01610] [EC:4.1.1.49]
HYN49_06540  pdhA; pyruvate dehydrogenase (acetyl-transferring) E1 component subunit alpha [KO:K00161] [EC:1.2.4.1]
HYN49_05985  pyruvate dehydrogenase complex E1 component subunit beta [KO:K00162] [EC:1.2.4.1]
HYN49_06545  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
fpal00010  Glycolysis / Gluconeogenesis
fpal00053  Ascorbate and aldarate metabolism
fpal00061  Fatty acid biosynthesis
fpal00071  Fatty acid degradation
fpal00190  Oxidative phosphorylation
fpal00220  Arginine biosynthesis
fpal00250  Alanine, aspartate and glutamate metabolism
fpal00280  Valine, leucine and isoleucine degradation
fpal00350  Tyrosine metabolism
fpal00470  D-Amino acid metabolism
fpal00630  Glyoxylate and dicarboxylate metabolism
KO pathway
ko00020   
LinkDB

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