ABSTRACT
Proteins are among the most versatile and active macromolecules in our living system. Proteins interact with one another and with each of the other three biomolecular classes: nucleic acids, lipids, and carbohydrates. Proteins are polypeptides built of amino acids, which are linked by covalent peptide bonds, to form long unbranched polymers. Besides contributing to the structure of proteins, glycine is necessary for our bodies to produce heme, which is necessary for the function of our iron-carrying molecules, hemoglobin, and myoglobin. Proteases are inherent in our digestive system, where they act on dietary proteins, reducing them to amino acids to be recycled in subsequent protein synthesis. The structure of many food products and dishes is greatly influenced by the properties of proteins, and changes on cooking or preparing food often result from changes such as heat-induced denaturation or changes in structure due to changing acidity or salt concentrations.
