羧基端由多個胺基酸殘基按一定順序所組成的多肽鏈，通常在一端含有一個游離的α氨基，稱為氨基端或N末A端或N端，另一端含有一個游離的α羧基，稱為羧基端或CA末端或C端。
肽的命名是根據參與其組成的胺基酸殘基來確定的，規定從肽鏈的氨基末端胺基酸殘基開始，稱為某氨醯某胺基酸等.例如，具有下列化學結構的五肽，命名為絲氨醯甘氨醯酪氨醯丙氨醯亮氨酸.SerGlyTyrAlaLeu。通常A總是把氨基末端胺基酸殘基放在左邊，羧基末端胺基酸殘基放在右邊，特別指出者除外.上邊舉例的五肽，如果反過來書寫，把亮氨酸寫在左邊，而把絲氨酸寫在最右邊，就變成另一個不同的五肽LeuAlaTyrGlySer。AAAA相 關 詞 條:細胞外基質|芋螺毒素 |胺基酸 |分子進化|By a number of amino acid residues composed of a certain sequence of polypeptide chain, usually at one end containing a free α-amino-acid called N-terminal or N terminal or N terminal end of A and the other end containing a free α-carboxyl group, saying for the carboxy-terminal end or C terminal, or CA. peptide involved in its name is based on the composition of amino acid residues to determine, the provisions of peptide chain from the N-terminal amino acid residues starting, called an aminoacyl certain amino acids, etc.. For example, with the following chemical structure of the 5 peptides, named seryl glycyl tyrosyl alanyl-leucine. SerGlyTyrAlaLeu. A usually always N-terminal amino acid residues on the left, carboxyl-terminal amino acid residues on the right side, in particular, pointed out that those other countries. Above example, the five peptides, if in turn, writing, written on the left side of the leucine and the serine written on the far right, it becomes a different five-peptide LeuAlaTyrGlySer. AAAA Related entries: extracellular matrix | Conotoxin | AminoAcid| molecular evolution |
