The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) refers to the start of a protein or polypeptide terminated by an amino acid with a free amine group (-NH2). The convention for writing peptide sequences's to put the N-terminus on the left and write the sequence from N- to C-terminus. When the protein's translated from messenger RNA, it's created from N-terminus to C-terminus. Chemistry Each amino acid has a carboxyl group and an amine group, and am… (More on N-terminus)