Proteins (Topical Term)

Oxford dict. of biochemistry and molecular biology, 2006 (protein: any of a large group of organic compounds found as major macromolecular constituents of living organisms. A protein is a linear polymer of amino acids linked by peptide bonds in a specific sequence. In the biosynthesis of the polypeptide chains, any of 20 different amino acids may be incorporated according to the genetic instructions of the cell.)

Facts on file dict. of biochemistry, 2003 (protein: one of a large number of substances that are important in the structure and function of all living organisms. Proteins are polypeptides; i.e., they are made up of amino acid molecules joined together by peptide links. Their molecular weight may vary from a few thousand to several million. About 20 amino acids are present in proteins. Proteins may consist of one or several polypeptide chains.)