What Are Proteins?

Proteins are large macromolecules that are made up of smaller units called amino acids, attached to form long chains. Proteins are required for maintaining the structure, function and regulation of the body's tissues and organs and can be described and categorized according to their function in the body.

Proteins can function as antibodies, which protect the body by binding to foreign particles; enzymes, which catalyze reactions in organisms; messengers, which coordinate biological processes in the body; structures to support the cell and provide motility; and transportation/storage in the cells. There are 20 different amino acids which can combine to form a protein, with the sequence determining the structure and function of the protein in the body.