PATHWAY: msyl00020 Help
Entry
Name
Citrate cycle (TCA cycle) - Malus sylvestris (European crab apple)
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
Other DBs
Organism
Malus sylvestris (European crab apple) [GN:
msyl ]
Gene
126587426 isocitrate dehydrogenase [NAD] regulatory subunit 1, mitochondrial-like isoform X1 [KO:K00030 ] [EC:1.1.1.41 ]
126602332 isocitrate dehydrogenase [NAD] regulatory subunit 1, mitochondrial-like isoform X1 [KO:K00030 ] [EC:1.1.1.41 ]
126583351 dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex 1, mitochondrial-like [KO:K00658 ] [EC:2.3.1.61 ]
126612294 dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex 1, mitochondrial-like isoform X1 [KO:K00658 ] [EC:2.3.1.61 ]
126615869 dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex 2, mitochondrial [KO:K00658 ] [EC:2.3.1.61 ]
126582347 succinate dehydrogenase [ubiquinone] iron-sulfur subunit 2, mitochondrial-like [KO:K00235 ] [EC:1.3.5.1 ]
126611496 succinate dehydrogenase [ubiquinone] iron-sulfur subunit 2, mitochondrial-like [KO:K00235 ] [EC:1.3.5.1 ]
126588622 succinate dehydrogenase subunit 3-1, mitochondrial-like [KO:K00236 ]
126611304 dihydrolipoyllysine-residue acetyltransferase component 2 of pyruvate dehydrogenase complex, mitochondrial-like [KO:K00627 ] [EC:2.3.1.12 ]
126629129 dihydrolipoyllysine-residue acetyltransferase component 1 of pyruvate dehydrogenase complex, mitochondrial-like [KO:K00627 ] [EC:2.3.1.12 ]
126588050 dihydrolipoyllysine-residue acetyltransferase component 5 of pyruvate dehydrogenase complex, chloroplastic-like [KO:K00627 ] [EC:2.3.1.12 ]
126619212 dihydrolipoyllysine-residue acetyltransferase component 1 of pyruvate dehydrogenase complex, mitochondrial-like isoform X1 [KO:K00627 ] [EC:2.3.1.12 ]
126622404 dihydrolipoyllysine-residue acetyltransferase component 5 of pyruvate dehydrogenase complex, chloroplastic-like [KO:K00627 ] [EC:2.3.1.12 ]
126595515 dihydrolipoyllysine-residue acetyltransferase component 4 of pyruvate dehydrogenase complex, chloroplastic-like [KO:K00627 ] [EC:2.3.1.12 ]
126608248 dihydrolipoyllysine-residue acetyltransferase component 4 of pyruvate dehydrogenase complex, chloroplastic-like [KO:K00627 ] [EC:2.3.1.12 ]
126581905 dihydrolipoyllysine-residue acetyltransferase component 2 of pyruvate dehydrogenase complex, mitochondrial-like [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
msyl00250 Alanine, aspartate and glutamate metabolism
msyl00280 Valine, leucine and isoleucine degradation
msyl00630 Glyoxylate and dicarboxylate metabolism
KO pathway
LinkDB
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