関連ワード:  what amino acids make up collagen    what amino acids make up collagen peptides    what 3 amino acids make up collagen    what amino acids make up type 1 collagen    what amino acids form collagen    which amino acids make up the structural protein collagen    what two amino acids make up almost all of collagen proteins    how many amino acids make up collagen    are amino acids in collagen    what is the main amino acid in collagen