KEGG   PATHWAY: bne00020
Entry
bne00020                    Pathway                                
Name
Citrate cycle (TCA cycle) - Brevundimonas naejangsanensis
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
bne00020  Citrate cycle (TCA cycle)
bne00020

Module
bne_M00003  Gluconeogenesis, oxaloacetate => fructose-6P [PATH:bne00020]
bne_M00009  Citrate cycle (TCA cycle, Krebs cycle) [PATH:bne00020]
bne_M00010  Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:bne00020]
bne_M00011  Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:bne00020]
bne_M00307  Pyruvate oxidation, pyruvate => acetyl-CoA [PATH:bne00020]
Other DBs
GO: 0006099
Organism
Brevundimonas naejangsanensis [GN:bne]
Gene
DA69_03720  citrate (Si)-synthase [KO:K01647] [EC:2.3.3.1]
DA69_12055  aconitate hydratase 1 [KO:K01681] [EC:4.2.1.3]
DA69_00550  isocitrate dehydrogenase [KO:K00031] [EC:1.1.1.42]
DA69_12930  2-oxoglutarate dehydrogenase E1 component [KO:K00164] [EC:1.2.4.2]
DA69_12935  dihydrolipoamide succinyltransferase [KO:K00658] [EC:2.3.1.61]
DA69_11100  dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
DA69_13680  dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
DA69_05775  dihydrolipoyl dehydrogenase [KO:K00382] [EC:1.8.1.4]
DA69_12925  succinate--CoA ligase subunit alpha [KO:K01902] [EC:6.2.1.5]
DA69_12920  succinate--CoA ligase subunit beta [KO:K01903] [EC:6.2.1.5]
DA69_06495  acetyl-CoA hydrolase [KO:K18118] [EC:2.8.3.18]
DA69_11905  succinate dehydrogenase flavoprotein subunit [KO:K00239] [EC:1.3.5.1]
DA69_11910  succinate dehydrogenase iron-sulfur subunit [KO:K00240] [EC:1.3.5.1]
DA69_11895  succinate dehydrogenase, cytochrome b556 subunit [KO:K00241]
DA69_11900  succinate dehydrogenase [KO:K00242]
DA69_03255  fumarate hydratase, class II [KO:K01679] [EC:4.2.1.2]
DA69_11885  malate dehydrogenase [KO:K00024] [EC:1.1.1.37]
DA69_02550  phosphoenolpyruvate carboxykinase [KO:K01596] [EC:4.1.1.32]
DA69_05800  pyruvate dehydrogenase (acetyl-transferring) E1 component subunit alpha [KO:K00161] [EC:1.2.4.1]
DA69_05795  pyruvate dehydrogenase complex E1 component subunit beta [KO:K00162] [EC:1.2.4.1]
DA69_05785  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
bne00010  Glycolysis / Gluconeogenesis
bne00053  Ascorbate and aldarate metabolism
bne00061  Fatty acid biosynthesis
bne00071  Fatty acid degradation
bne00190  Oxidative phosphorylation
bne00220  Arginine biosynthesis
bne00250  Alanine, aspartate and glutamate metabolism
bne00280  Valine, leucine and isoleucine degradation
bne00350  Tyrosine metabolism
bne00470  D-Amino acid metabolism
bne00630  Glyoxylate and dicarboxylate metabolism
KO pathway
ko00020   
LinkDB

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