HYDROGEN-BONDING IN BIOLOGICAL MOLECULES - AN UPDATE

High-precision neutron structures of amino acids and small peptides are analyzed to obtain information on the hydrogen bonding characteristics of various functional groups in these structures. The influence of donor and acceptor groups on H-bond parameters and the conformational flexibility of protonated amino groups in the context of H-bonding are some of the results obtained. Relative H-bonding capabilities of oxygen-containing H-bonding groups are analyzed using H-bond populations and bond strength criteria. An application of these ideas to two active-site residues in lysozyme is discussed.