What is a chain of amino acids connected by peptide bonds known as?

A chain of amino acids connected by peptide bonds is known as a polypeptide. This term specifically describes a longer sequence of amino acids that are linked together through peptide bonds, which form when the carboxyl group of one amino acid reacts with the amino group of another, releasing a water molecule in the process.

While the term "peptide" generally refers to shorter chains of amino acids (typically fewer than 50), "polypeptide" is used for longer chains. Once polypeptides fold into specific three-dimensional structures and achieve functional shape, they can be referred to as proteins. Therefore, polypeptide denotes the arrangement of amino acids specifically in the context of being a chain of various lengths, before they assume the functional form as proteins.

The term "enzyme" refers to a specific type of protein that acts as a catalyst in biochemical reactions but is not synonymous with a chain of amino acids.