polypeptide

A *peptide chain containing a large number of amino acid residues (most polypeptides have a molecular weight greater than 5000). *Proteins are made up of one or more polypeptides.
The amino acid sequence of a polypeptide chain determines the three-dimensional conformation of that molecule under physiological conditions. This conformation can be disrupted by heating or extremes of pH (see denaturation ). See also conjugated protein.