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

Types of reactions catalyzed by enzymes
A brief overview of certain metabolic pathways
Biosynthesis

While consuming nutrients to generate energy, Cells are at the same time continuously building new material. In Fig. 7-1, the dashed lines indicate the metabolic pathways by which these synthesis processes are carried out. If we return to the right-hand side of Fig. 7-1, we will see that the fatty acid synthesis pathway begins with acetyl-CoA and represents a Reversal of the fatty acid degradation pathway. However, synthesis requires ATP as an energy source and carbon dioxide. In addition, whereas Fatty acid oxidation requires NAD+ as one of the oxidizing agents, which is thereby converted to NADH, biosynthetic processes often involve the related hydrogen carrier NADPH. The situation observed in fatty acid synthesis is typical. Synthetic reactions resemble catabolic sequences running in reverse, yet certain differences between synthetic and catabolic reactions are nonetheless evident. These are typically related to Energy Requirements and control mechanisms.



Last update: 06/08/2026

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