polüpeptiidahela

A polüpeptiidahela, or polypeptide chain, is a linear sequence of amino acids linked together by peptide bonds. These chains are the fundamental building blocks of proteins. Each amino acid in the chain has a unique side chain, which influences the overall properties of the polypeptide. The sequence of amino acids is determined by the genetic code, transcribed from messenger RNA (mRNA) during the process of translation.

The formation of a peptide bond occurs through a dehydration reaction, where a water molecule is removed as the carboxyl group of one amino acid reacts with the amino group of another. A polypeptide chain has a defined directionality, with an amino terminus (N-terminus) and a carboxyl terminus (C-terminus). The specific order of amino acids, known as the primary structure, dictates how the polypeptide will fold into its three-dimensional, functional shape. This folding process, driven by interactions between amino acid side chains, leads to secondary, tertiary, and sometimes quaternary structures, which are essential for protein function. A polüpeptiidahela can range in length from a few amino acids to hundreds or even thousands.