prótein
Prótein is a biological macromolecule composed of one or more polypeptide chains folded into a specific three-dimensional shape. In all living organisms proteins perform a vast array of vital roles and are built from long sequences of amino acids linked by peptide bonds. The properties of a protein arise from its sequence and three-dimensional structure.
Proteins have a hierarchy of structure: the primary structure is the amino acid sequence. Higher levels include
There are twenty standard amino acids that form proteins. Nine are essential in adult humans and must
Dietary proteins supply amino acids for maintenance and growth. Animal sources such as meat, dairy, and eggs
In biology and industry, proteins function as enzymes, antibodies, hormones, and therapeutic agents; they are used