TCA cycle (aka Krebs or citric acid cycle) (WP78)

The [[wikipedia:citric_acid_cycle|citric acid cycle]], also known as the tricarboxylic acid cycle (TCA cycle) or the Krebs cycle, (or rarely, the Szent-Gyorgyi-Krebs cycle) is a series of enzyme-catalysed chemical reactions of central importance in all living cells that use oxygen as part of cellular respiration. In eukaryotes, the citric acid cycle occurs in the matrix of the mitochondrion. The components and reactions of the citric acid cycle were established by seminal work from both [[wikipedia:Albert_Szent-Gyorgyi|Albert Szent-Gyorgyi]] and [[wikipedia:Hans_Krebs|Hans Krebs]]. Source: Wikipedia ([[wikipedia:citric_acid_cycle]]) Proteins on this pathway have targeted assays available via the [https://assays.cancer.gov/available_assays?wp_id=WP78 CPTAC Assay Portal].
last edited

Authors

Kdahlquist, MaintBot, MartijnVanIersel, AlexanderPico, Thomas, N.Fidelman, Khanspers, Ray Andrews II, HarmNijveen, Mdstobbe, Smhouten, Ddigles, Egonw, DeSl, Finterly, and Eweitz

Cited In

Organism

Homo sapiens

Communities

Annotations

Pathway Ontology: citric acid cycle pathway classic metabolic pathway citric acid cycle pathway

Participants

Label Type Compact Identifier
GTP Metabolite hmdb:HMDB0001273
GDP Metabolite hmdb:HMDB0001201
CO2 Metabolite hmdb:HMDB0001967
water Metabolite hmdb:HMDB0002111
NADH Metabolite hmdb:HMDB0001487
oxaloacetate Metabolite hmdb:HMDB0000223
IDH3B GeneProduct ncbigene:3420
ubiquinone-10 Metabolite hmdb:HMDB0001072
NADH Metabolite hmdb:HMDB0001487
cis-aconitate Metabolite hmdb:HMDB0000072
water Metabolite hmdb:HMDB0002111
Degradation of Fatty Acids Pathway wikipathways:WP143
NADP Metabolite hmdb:HMDB0000217
SDHA GeneProduct ncbigene:6389
D-threo-Isocitrate Metabolite hmdb:HMDB0000193
Metabolism of amino acids Pathway wikipathways:WP1847
NAD Metabolite hmdb:HMDB0000902
SUCLG2 GeneProduct ncbigene:8801
ACO2 GeneProduct ncbigene:50
water Metabolite hmdb:HMDB0002111
ubiquinol-10 Metabolite hmdb:HMDB0013111
(S)-malate Metabolite hmdb:HMDB0000156
SUCLG1 GeneProduct ncbigene:8802
DLST GeneProduct ncbigene:1743
succinate Metabolite hmdb:HMDB0000254
ATP Metabolite hmdb:HMDB0000538
IDH3G GeneProduct ncbigene:3421
SDHC GeneProduct ncbigene:6391
ACO2 GeneProduct ncbigene:50
CoA Metabolite hmdb:HMDB0001423
NAD Metabolite hmdb:HMDB0000902
acetyl-CoA Metabolite hmdb:HMDB0001206
2-oxoglutarate Metabolite hmdb:HMDB0000208
IDH2 GeneProduct ncbigene:3418
SDHD GeneProduct ncbigene:6392
Electron Transport Chain Pathway wikipathways:WP111
CoA Metabolite hmdb:HMDB0001423
SDHB GeneProduct ncbigene:6390
ADP Metabolite hmdb:HMDB0001341
NADPH Metabolite hmdb:HMDB0000221
CS GeneProduct ncbigene:1431
citrate Metabolite hmdb:HMDB0000094
CoA Metabolite hmdb:HMDB0001423
NAD Metabolite hmdb:HMDB0000902
IDH3A GeneProduct ncbigene:3419
Urea cycle Pathway wikipathways:WP497
DLD GeneProduct ncbigene:1738
Fatty Acid Synthesis Pathway wikipathways:WP357
NADH Metabolite hmdb:HMDB0001487
OGDH GeneProduct ncbigene:4967
Glucose metabolism Pathway wikipathways:WP534
FH GeneProduct ncbigene:2271
fumarate Metabolite hmdb:HMDB0000134
MDH2 GeneProduct ncbigene:4191
succinyl-CoA Metabolite hmdb:HMDB0001022
CO2 Metabolite hmdb:HMDB0001967
CO2 Metabolite hmdb:HMDB0001967
Pi Metabolite hmdb:HMDB0001429
water Metabolite hmdb:HMDB0002111
CoA Metabolite hmdb:HMDB0001423
Pi Metabolite hmdb:HMDB0001429
SUCLA2 GeneProduct uniprot:Q9P2R7
SUCLG1 GeneProduct ncbigene:8802

References

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  3. Gabriel JL, Zervos PR, Plaut GW. Activity of purified NAD-specific isocitrate dehydrogenase at modulator and substrate concentrations approximating conditions in mitochondria. Metabolism. 1986 Jul;35(7):661–7. PubMed Europe PMC Scholia
  4. Krebs HA, Johnson WA. The role of citric acid in intermediate metabolism in animal tissues. FEBS Lett. 1980 Aug 25;117 Suppl:K1-10. PubMed Europe PMC Scholia
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  6. Des Rosiers C, Di Donato L, Comte B, Laplante A, Marcoux C, David F, et al. Isotopomer analysis of citric acid cycle and gluconeogenesis in rat liver. Reversibility of isocitrate dehydrogenase and involvement of ATP-citrate lyase in gluconeogenesis. J Biol Chem. 1995 Apr 28;270(17):10027–36. PubMed Europe PMC Scholia
  7. Fernandez CA, Des Rosiers C. Modeling of liver citric acid cycle and gluconeogenesis based on 13C mass isotopomer distribution analysis of intermediates. J Biol Chem. 1995 Apr 28;270(17):10037–42. PubMed Europe PMC Scholia
  8. Des Rosiers C, Fernandez CA, David F, Brunengraber H. Reversibility of the mitochondrial isocitrate dehydrogenase reaction in the perfused rat liver. Evidence from isotopomer analysis of citric acid cycle intermediates. J Biol Chem. 1994 Nov 4;269(44):27179–82. PubMed Europe PMC Scholia
  9. Sazanov LA, Jackson JB. Proton-translocating transhydrogenase and NAD- and NADP-linked isocitrate dehydrogenases operate in a substrate cycle which contributes to fine regulation of the tricarboxylic acid cycle activity in mitochondria. FEBS Lett. 1994 May 16;344(2–3):109–16. PubMed Europe PMC Scholia
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  11. Johnson JD, Muhonen WW, Lambeth DO. Characterization of the ATP- and GTP-specific succinyl-CoA synthetases in pigeon. The enzymes incorporate the same alpha-subunit. J Biol Chem. 1998 Oct 16;273(42):27573–9. PubMed Europe PMC Scholia
  12. Sheu KF, Blass JP. The alpha-ketoglutarate dehydrogenase complex. Ann N Y Acad Sci. 1999;893:61–78. PubMed Europe PMC Scholia
  13. Comte B, Vincent G, Bouchard B, Benderdour M, Des Rosiers C. Reverse flux through cardiac NADP(+)-isocitrate dehydrogenase under normoxia and ischemia. Am J Physiol Heart Circ Physiol. 2002 Oct;283(4):H1505-14. PubMed Europe PMC Scholia
  14. KREBS HA, HOLZACH O. The conversion of citrate into cis-aconitate and isocitrate in the presence of aconitase. Biochem J. 1952 Nov;52(3):527–8. PubMed Europe PMC Scholia
  15. Lambeth DO, Tews KN, Adkins S, Frohlich D, Milavetz BI. Expression of two succinyl-CoA synthetases with different nucleotide specificities in mammalian tissues. J Biol Chem. 2004 Aug 27;279(35):36621–4. PubMed Europe PMC Scholia