Principles of Biochemistry, Volume 1 - A. Lehninger 1985

Biomolecules
Vitamins and trace elements: their role in enzyme function
Vitamins can be divided into two classes

Vitamins are divided into two classes: Water-soluble and Fat-soluble vitamins (Table 10-1). Water-Soluble Vitamins include thiamine (Vitamin B1), riboflavin (vitamin B2), nicotinic acid, pantothenic acid, pyridoxine (vitamin B6), biotin, folic acid, vitamin B12, and ascorbic acid (Vitamin C). The coenzyme Functions of nearly all of these vitamins have been well established. The biochemical Functions of the fat-soluble vitamins A, D, E, and K—which are oily substances with low water solubility—are not yet fully understood. In addition to these well-known vitamins, there are other substances required by specific species that are not typically classified as vitamins. These include carnitine (Section 18.2), Inositol, and Lipoic Acid (Chapter 26).

First, we will examine The Nature and properties of water-soluble VITAMINS AND THEIR roles as components of various Coenzymes, as well as provide Examples of the enzymatic reactions in which these coenzymes participate (Table 10-1).



Last update: 06/08/2026

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