KEGG   PATHWAY: lca00020Help
lca00020                    Pathway                                

Citrate cycle (TCA cycle) - Lactobacillus paracasei ATCC 334
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
lca00020  Citrate cycle (TCA cycle)

Ortholog table
lca_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:lca00020]
lca_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:lca00020]
Other DBs
BSID: 39995
GO: 0006099
Lactobacillus paracasei ATCC 334 [GN:lca]
LSEI_1446  acetoin/pyruvate dehydrogenase complex, E3 component, dihydrolipoamide dehydrogenase [KO:K00382] [EC:]
LSEI_1308  dihydrolipoamide dehydrogenase [KO:K00382] [EC:]
LSEI_0322  fumarate reductase flavoprotein subunit [KO:K00244] [EC:]
LSEI_2410  fumC; fumarate hydratase [KO:K01679] [EC:]
LSEI_1315  pyruvate carboxylase [KO:K01958] [EC:]
LSEI_1820  phosphoenolpyruvate carboxykinase [KO:K01610] [EC:]
LSEI_1305  acetoin dehydrogenase complex, E1 component subunit alpha [KO:K00161] [EC:]
LSEI_1306  acetoin dehydrogenase complex, E1 component subunit beta [KO:K00162] [EC:]
LSEI_1307  dihydrolipoamide acetyltransferase [KO:K00627] [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

DBGET integrated database retrieval system