PATHWAY: omy00020 Help
Entry
Name
Citrate cycle (TCA cycle) - Oncorhynchus mykiss (rainbow trout)
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
omy_M00010 Citrate cycle, first carbon oxidation, oxaloacetate => 2-oxoglutarate [PATH:omy00020 ]
omy_M00011 Citrate cycle, second carbon oxidation, 2-oxoglutarate => oxaloacetate [PATH:omy00020 ]
Other DBs
Organism
Oncorhynchus mykiss (rainbow trout) [GN:
omy ]
Gene
110526099 ogdha; oxoglutarate (alpha-ketoglutarate) dehydrogenase a (lipoamide) isoform X1 [KO:K00164 ] [EC:1.2.4.2 ]
110522634 dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial isoform X1 [KO:K00658 ] [EC:2.3.1.61 ]
110529281 LOW QUALITY PROTEIN: dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial [KO:K00658 ] [EC:2.3.1.61 ]
110497925 dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial isoform X1 [KO:K00658 ] [EC:2.3.1.61 ]
110505539 dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial [KO:K00658 ] [EC:2.3.1.61 ]
110488064 succinate dehydrogenase [ubiquinone] flavoprotein subunit, mitochondrial isoform X1 [KO:K00234 ] [EC:1.3.5.1 ]
110528062 succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial isoform X1 [KO:K00235 ] [EC:1.3.5.1 ]
110492247 succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial isoform X1 [KO:K00235 ] [EC:1.3.5.1 ]
110494374 sdhb; succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial [KO:K00235 ] [EC:1.3.5.1 ]
110508324 succinate dehydrogenase cytochrome b560 subunit, mitochondrial isoform X2 [KO:K00236 ]
110530767 sdhc; succinate dehydrogenase cytochrome b560 subunit, mitochondrial isoform X1 [KO:K00236 ]
110503765 succinate dehydrogenase [ubiquinone] cytochrome b small subunit B, mitochondrial [KO:K00237 ]
110507178 succinate dehydrogenase [ubiquinone] cytochrome b small subunit B, mitochondrial [KO:K00237 ]
110535379 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial isoform X1 [KO:K00161 ] [EC:1.2.4.1 ]
110489633 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial-like isoform X1 [KO:K00161 ] [EC:1.2.4.1 ]
110510070 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial isoform X1 [KO:K00161 ] [EC:1.2.4.1 ]
110534083 pyruvate dehydrogenase E1 component subunit alpha, mitochondrial isoform X2 [KO:K00161 ] [EC:1.2.4.1 ]
110509478 dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex, mitochondrial [KO:K00627 ] [EC:2.3.1.12 ]
110533249 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
omy00053 Ascorbate and aldarate metabolism
omy00250 Alanine, aspartate and glutamate metabolism
omy00280 Valine, leucine and isoleucine degradation
omy00630 Glyoxylate and dicarboxylate metabolism
KO pathway
LinkDB
All DBs