On the similarity of properties in solution or in the crystalline state: Amolecular dynamics study of hen lysozyme

As protein crystals generally possess a high water content, it is assumed t hat the behaviour of a protein in solution and in crystal environment is ve ry similar. This assumption can be investigated by molecular dynamics (MD) simulation of proteins in the different environments. Two 2ns simulations o f hen egg white lysozyme (HEWL) in crystal and solution environment are com pared to one another and to experimental data derived from both X-ray and N MR experiments, such as crystallographic B-factors, NOE atom-atom distance bounds, (3)J(H) N alpha-coupling constants, and H-1-N-15 bond vector order parameters. Both MD simulations give very similar results. The crystal simu lation reproduces X-ray and NMR data slightly better than the solution simu lation.