Elementary plant Biochemistry and Biotechnology (2+1)

d) Amino acids with charged R groups

• Acidic: The two amino acids with acidic R groups are aspartic and glutamic acids. These amino acids have a net negative charge at pH 7.0.
• Basic: This group includes lysine, arginine and histidine . The R groups have a net positive charge at pH 7.0. The lysine has a second Σ-amino group; arginine has a positively charged guanidino group; and histidine has an imidazole group.