Definition of polypeptide in English:


Pronunciation /ˌpälēˈpeptīd/ /ˌpɑliˈpɛptaɪd/


  • A linear organic polymer consisting of a large number of amino-acid residues bonded together in a chain, forming part of (or the whole of) a protein molecule.

    as modifier ‘a polypeptide chain’
    • ‘It is a basic protein with a single polypeptide chain and acts on cellular and model lipid membranes.’
    • ‘These enzymes break down proteins into polypeptides and then into amino acids, which are absorbed through the gut wall into the bloodstream.’
    • ‘They both develop random transient beta-strands across the whole polypeptide chain.’
    • ‘The LDL receptor is a polypeptide of 839 amino acids that spans the plasma membrane.’
    • ‘Unlike larger polypeptides and proteins, small nucleic acid duplexes and hairpins do not have a dense core to which this effect would apply.’


Early 20th century from poly-‘many’ + peptone+ -ide.