PATHWAY: oke00020 Help
Entry
Name
Citrate cycle (TCA cycle) - Oncorhynchus keta (chum salmon)
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
BRITE hierarchy
Pathway map
Ortholog table
Module
oke_M00010 Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:oke00020 ]
oke_M00011 Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:oke00020 ]
Other DBs
Organism
Oncorhynchus keta (chum salmon) [GN:
oke ]
Gene
127928977 idh3a; LOW QUALITY PROTEIN: isocitrate dehydrogenase [NAD] subunit alpha, mitochondrial [KO:K00030 ] [EC:1.1.1.41 ]
118393599 ogdha; oxoglutarate (alpha-ketoglutarate) dehydrogenase a (lipoamide) isoform X1 [KO:K00164 ] [EC:1.2.4.2 ]
118362484 dlst; dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial isoform X1 [KO:K00658 ] [EC:2.3.1.61 ]
118374099 dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial-like [KO:K00658 ] [EC:2.3.1.61 ]
118381046 succinate dehydrogenase [ubiquinone] flavoprotein subunit, mitochondrial-like [KO:K00234 ] [EC:1.3.5.1 ]
118400263 succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial-like [KO:K00235 ] [EC:1.3.5.1 ]
118381588 succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial-like isoform X1 [KO:K00235 ] [EC:1.3.5.1 ]
118359776 succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial isoform X1 [KO:K00235 ] [EC:1.3.5.1 ]
118394942 sdhc; succinate dehydrogenase cytochrome b560 subunit, mitochondrial isoform X1 [KO:K00236 ]
118376223 succinate dehydrogenase cytochrome b560 subunit, mitochondrial-like [KO:K00236 ]
118373670 succinate dehydrogenase [ubiquinone] cytochrome b small subunit B, mitochondrial-like [KO:K00237 ]
118397338 succinate dehydrogenase [ubiquinone] cytochrome b small subunit B, mitochondrial-like [KO:K00237 ]
118385037 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial isoform X1 [KO:K00161 ] [EC:1.2.4.1 ]
118361709 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial-like isoform X1 [KO:K00161 ] [EC:1.2.4.1 ]
118390452 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial-like isoform X1 [KO:K00161 ] [EC:1.2.4.1 ]
118369785 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial-like isoform X1 [KO:K00161 ] [EC:1.2.4.1 ]
118371843 LOW QUALITY PROTEIN: dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex, mitochondrial-like [KO:K00627 ] [EC:2.3.1.12 ]
118389736 dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex, mitochondrial [KO:K00627 ] [EC:2.3.1.12 ]
Compound
C05125 2-(alpha-Hydroxyethyl)thiamine diphosphate
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
oke00053 Ascorbate and aldarate metabolism
oke00250 Alanine, aspartate and glutamate metabolism
oke00280 Valine, leucine and isoleucine degradation
oke00630 Glyoxylate and dicarboxylate metabolism
KO pathway
LinkDB
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