Biochemistry: The Chemical Reactions of Living Cells, Volume 2 - D. Metzler 1980

Coenzymes: Specialized Natural Reagents
Lipoic Acid and the Oxidative Decarboxylation of α-Keto Acids
Cleavage of α-Keto Acids and Substrate-Level Phosphorylation

α-Keto acid dehydrogenases produce CoA derivatives that can enter biosynthetic reactions. On the other hand, acyl-CoA derivatives can be cleaved to yield ATP. The Pyruvate-formate-lyase system also constitutes part of the ATP-generating system in anaerobic organisms [e.g., in the "Mixed Acid Fermentation" of enterobacteria, including E. coli (Chap. 9, Sect. E, 2)]. These two reactions represent a pair of important processes that provide substrate-level phosphorylation. For this reason, they are highlighted in Fig. 8-19. They should be compared with the two previously discussed Examples of substrate-level phosphorylation (Figs. 8-4 and 8-3).



Last update: 06/08/2026

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