The structure of amino acids in solution
16 Oct 2008



Self-organisation of proteins in solution and their aqueous environment.

Distribution of water around the carboxylate group in glutamic acid. Between the two oxygen atoms (red) a water molecule shares a hydrogen bond with both atoms.

Understanding how the self-organisation of a protein in solution is affected by its aqueous environment is a major challenge which has a long history. Unlike recent studies which have determined atomic-scale structural information in solid state proteins, the application of diffraction techniques to the study of protein hydration and conformation in solution at atomic-scale resolution is limited. In preparation for a wider programme to look at the conformation of oligopeptides and other biological molecules in solution, we have initiated a study of single amino acids, glutamic acid and proline, in solution. Glutamic acid is a neurotransmitter and the investigation provides information specific to receptor binding. Glutamic acid is also the precursor for proline, which was chosen as it occurs in most proteins and is believed to be the smallest known enzyme. These two systems have been investigated using neutron diffraction with isotopic substitution and combined with computer modelling, in order to elucidate the conformation of these amino acids in solution and their interaction with the aqueous environment.

SE McLain (ISIS and University of Oxford), AK Soper (ISIS) and A Watts (University of Oxford)

Research date: December 2006

Further Information

Dr S E McLain
S E McLain et al., J. Chem. Phys. B110 (2006) 21251​