The primary structure of a protein is determined by the sequence of amino acids that make up the polypeptide chain. This sequence is dictated by the genetic information encoded in DNA.
During the process of transcription, a specific segment of DNA is copied into messenger RNA (mRNA). This mRNA then undergoes translation, where ribosomes read the nucleotide sequence in sets of three (codons) and assemble the corresponding amino acids into a polypeptide chain based on the genetic template.
Each amino acid is linked to the next by peptide bonds, resulting in a unique linear sequence that defines the protein’s identity and function. The specific order of amino acids is crucial because it not only influences the protein’s shape but also its biochemical properties and how it interacts with other molecules.