KEGG   PATHWAY: bqu00020Help
bqu00020                    Pathway                                

Citrate cycle (TCA cycle) - Bartonella quintana Toulouse
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
bqu00020  Citrate cycle (TCA cycle)

Ortholog table
bqu_M00009  Citrate cycle (TCA cycle, Krebs cycle) [PATH:bqu00020]
bqu_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:bqu00020]
bqu_M00011  Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:bqu00020]
bqu_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:bqu00020]
Other DBs
BSID: 17607
GO: 0006099
Bartonella quintana Toulouse [GN:bqu]
BQ06850  gltA; Citrate synthase [KO:K01647] [EC:]
BQ01090  acnA; Aconitate hydratase [KO:K01681] [EC:]
BQ07780  icdA; NADP-dependent isocitrate dehydrogenase [KO:K00031] [EC:]
BQ13420  sucA; Alpha-ketoglutarate dehydrogenase [KO:K00164] [EC:]
BQ13410  sucB; Dihydrolipoamide succinyltransferase [KO:K00658] [EC:]
BQ13400  pdhD1; Dihydrolipoamide dehydrogenase [KO:K00382] [EC:]
BQ04940  pdhD2; Dihydrolipoamide dehydrogenase [KO:K00382] [EC:]
BQ13430  sucD; Succinyl-CoA synthetase alpha chain [KO:K01902] [EC:]
BQ13440  sucC; Succinyl-CoA synthetase beta chain [KO:K01903] [EC:]
BQ12700  sdhA; Succinate dehydrogenase, flavoprotein subunit [KO:K00239] [EC:]
BQ12690  sdhB; Succinate dehydrogenase, iron-sulfur protein [KO:K00240] [EC:]
BQ12720  sdhC; Succinate dehydrogenase cytochrome b560 subunit [KO:K00241]
BQ12710  sdhD; Succinate dehydrogenase hydrophobic membrane anchor protein [KO:K00242]
BQ10770  fumC; Fumarate hydratase c [KO:K01679] [EC:]
BQ13450  mdh; Malate dehydrogenase [KO:K00024] [EC:]
BQ04910  pdhA; Pyruvate dehydrogenase E1 component, alpha subunit [KO:K00161] [EC:]
BQ04920  pdhB; Pyruvate dehydrogenase E1 component beta subunit [KO:K00162] [EC:]
BQ04930  pdhC; Dihydrolipoamide acetyltransferase (E2) [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
LinkDB All DBs

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