Dynamics of protein domains

We investigate the internal domain motion of proteins in order to clarify its role for the protein function. The motion is observed by high resolution neutron spectroscopy of a dilute aqueous solution with a spin-echo spectrometer. After assessing translational and rotational diffusion, the observed excess dynamics is characteristic for the fluctuations of larger domains, for example connected molecular structures that form a hinge. The observed dynamical structure factor is compared with computed normal modes of the molecules. With our technique, amplitudes and typical times of motions that enable or sustain the biological functions of a protein can be measured. (figure: R. Biehl et al., Phys. Rev Lett 101, 138102 (2008))

Neutron Scattering:
Ralf Biehl, Michael Monkenbusch, Dieter Richter