KEGG   PATHWAY: pshi00020
Entry
pshi00020                   Pathway                                
Name
Citrate cycle (TCA cycle) - Plesiomonas shigelloides
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
pshi00020  Citrate cycle (TCA cycle)
pshi00020

Module
pshi_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:pshi00020]
pshi_M00009  Citrate cycle (TCA cycle, Krebs cycle) [PATH:pshi00020]
pshi_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:pshi00020]
pshi_M00011  Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:pshi00020]
pshi_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:pshi00020]
Other DBs
GO: 0006099
Organism
Plesiomonas shigelloides [GN:pshi]
Gene
SAMEA2665130_2198  gltA; Citrate synthase [KO:K01647] [EC:2.3.3.1]
SAMEA2665130_0424  acnB; Aconitate hydratase 2 [KO:K01682] [EC:4.2.1.3 4.2.1.99]
SAMEA2665130_1662  icd; Isocitrate dehydrogenase [NADP] [KO:K00031] [EC:1.1.1.42]
SAMEA2665130_2193  sucA; 2-oxoglutarate dehydrogenase E1 component [KO:K00164] [EC:1.2.4.2]
SAMEA2665130_2192  sucB; Dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex [KO:K00658] [EC:2.3.1.61]
SAMEA2665130_2833  lpd; Dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
SAMEA2665130_0415  lpdA; Dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
SAMEA2665130_2190  sucD; Succinyl-CoA ligase [ADP-forming] subunit alpha [KO:K01902] [EC:6.2.1.5]
SAMEA2665130_2191  sucC; Succinyl-CoA ligase [ADP-forming] subunit beta [KO:K01903] [EC:6.2.1.5]
SAMEA2665130_2195  sdhA; Succinate dehydrogenase flavoprotein subunit [KO:K00239] [EC:1.3.5.1]
SAMEA2665130_2194  sdhB; Succinate dehydrogenase iron-sulfur subunit [KO:K00240] [EC:1.3.5.1]
SAMEA2665130_2197  sdhC; Succinate dehydrogenase cytochrome b556 subunit [KO:K00241]
SAMEA2665130_2196  sdhD; Succinate dehydrogenase hydrophobic membrane anchor subunit [KO:K00242]
SAMEA2665130_2754  frdA; Fumarate reductase flavoprotein subunit [KO:K00244] [EC:1.3.5.1]
SAMEA2665130_2755  frdB; Fumarate reductase iron-sulfur subunit [KO:K00245] [EC:1.3.5.1]
SAMEA2665130_2756  frdC; Fumarate reductase 15 kDa hydrophobic protein [KO:K00246]
SAMEA2665130_2757  frdD; Fumarate reductase 13 kDa hydrophobic protein [KO:K00247]
SAMEA2665130_1884  fumB; Fumarate hydratase class I, anaerobic [KO:K01676] [EC:4.2.1.2]
SAMEA2665130_2688  mdh; Malate dehydrogenase [KO:K00024] [EC:1.1.1.37]
SAMEA2665130_0197  pckA; Phosphoenolpyruvate carboxykinase [ATP] [KO:K01610] [EC:4.1.1.49]
SAMEA2665130_0413  aceE; Pyruvate dehydrogenase E1 component [KO:K00163] [EC:1.2.4.1]
SAMEA2665130_0414  aceF; Dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex [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
pshi00010  Glycolysis / Gluconeogenesis
pshi00053  Ascorbate and aldarate metabolism
pshi00061  Fatty acid biosynthesis
pshi00071  Fatty acid degradation
pshi00190  Oxidative phosphorylation
pshi00220  Arginine biosynthesis
pshi00250  Alanine, aspartate and glutamate metabolism
pshi00280  Valine, leucine and isoleucine degradation
pshi00350  Tyrosine metabolism
pshi00470  D-Amino acid metabolism
pshi00630  Glyoxylate and dicarboxylate metabolism
KO pathway
ko00020   
LinkDB

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