Chemistry and Sources of Protein
Document Type
Book Chapter
Publication Date
2025
Abstract
Constituted from the peptide bonds among 20 different amino acids, proteins play a wide range of roles in biological organisms, including: structural; enzymatic; hormonal; locomotory; and transport roles, among others. Their primary level of variability exists in the sequence of those 20 different amino acids in any peptide chain, which itself can vary in the number of amino acids. This sequence variability affects localized secondary structures, which then affect tertiary structures, which can then lead on to affecting quaternary structures of larger proteins. The chemical differences in the side-chain structures of each of the 20 amino acids provides the basis for all this variability. All amino acids can be synthesized de novo by both plants and bacteria. However, of those 20 amino acids, most animals can only synthesize about half (10), with the other half needing to be obtained via the diet, these constitute the dietary essential amino acids (EAA). Of the nonEAA, most have distinct pathways that utilize carbon and nitrogen from other amino acids, or even other macro-nutrients to be synthesized. To obtain dietary EAA, animals need to be provided with a certain level of EAA supply, and usually this is done through the provision of an EAA balanced level of protein in their diets. This protein needs to be provided usually from plant, bacterial or other animal sources. Using each of these sources of protein comes with their own distinct challenges notwithstanding, the EAA balance of most dietary proteins is not optimal, and so a blend of protein sources is often required.
Recommended Citation
Kumar, V., Ragaza, J. A., Glencross, B. (2025). Chemistry and Sources of Protein. In V. Kumar (Ed.), Nutrition and Physiology of Fish and Shellfish: Feed Regulation, Metabolism and Digestion (pp. 15-41). Elsevier. https://archium.ateneo.edu/
