Space-filling model of N5,N10-methylenetetrahydrofolate.
N5,N10-methylenetetrahydrofolate is used by the body to carry single-carbon units to anabolic processes which need to increase the number of carbon atoms in a biomolecule by one (e.g., conversion of glycine to serine). Tetrahydrofolate (the form lacking the extra carbon) is used in catabolic processes to break down biomolecules by removing a carbon from them.
Schematic diagram illustrating the four stages of catabolism.
The four stages of catabolism are: digestion (hydrolysis), conversion to citric acid cycle feedstocks, citric acid cycle catabolism, and oxidative phosphorylation.
figure, 25.1, stages, catabolism
Table 25.1 The Vitamins, their Coenzymes and their Chemical Functions