The Biology Project - Biochemistry The Biology Project Biochemistry

The Biology Project > Biochemistry > The Chemistry of Amino Acids

Close window

Basic Amino Acids

Basic amino acids are polar and positively charged at pH values below their pKa's, and are very hydrophilic. Even though the basic amino acids are almost always in contact with the solvent, the side chain of lysine has a marked hydrocarbon character, so it is often found NEAR the surface, with the amino group of the side chain in contact with solvent. Note that in the drawing, histidine is shown in the protonated form, while at pH 7.0, the imidazole would exist predominantly in the neutral form.
Molecular structure for histidine NH-CH=N-CH=C-CH2-CH(NH3)-COO Molecular structure for lysine H2N-(CH2)4-CH(NH3)-COO Molecular structure of arginine HN=C(NH2)-NH-(CH2)3-CH(NH3)-COO
Chemical structure of histidine Chemical structure for lysine Chemical structure for arginine

Close window

The Biology Project > Biochemistry > The Chemistry of Amino Acids

The Biology Project
Department of Biochemistry and Molecular Biophysics
University of Arizona
August 25, 2003
Contact the Development Team

http://biology.arizona.edu
All contents copyright © 2003. All rights reserved.