Berlin 2005 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
CPP: Chemische Physik und Polymerphysik
CPP 26: Biological systems II
CPP 26.2: Talk
Tuesday, March 8, 2005, 15:30–15:45, TU C230
Accessibility and intramolecular mobility of residues in native and non-native proteins as studied by time-resolved CIDNP — •Alexandra Yurkovskaya1, Olga Morozova1, Peter Hore2, and Hans-Martin Vieth3 — 1International Tomography Center of SB RAS, 630090, Institutskaya 3a, Novosibirsk, Russia — 2University of Oxford, South Parks Road, Oxford, OX1 3QH, UK — 3Department of Physics, Free University of Berlin, D-14195 Berlin, Germany
Among the magnetic resonance methods used for investigating the structure and dynamics of proteins in their native and non-native states the Chemically Induced Dynamic Nuclear Polarization (CIDNP) technique allows the selective spectroscopy of specific amino acid residues located on the protein surface. Its use for exploring the solvent-exposure, reactivity and dynamic properties of tryptophan and tyrosine residues for the comparative study of the native, partly folded and denatured states of small monomeric proteins will be presented. As a novel application the kinetics of the dynamic nuclear polarization formed by electron transfer and detected by high-resolution NMR in the diamagnetic state of the proteins allows determination of the paramagnetic nuclear spin-lattice relaxation times (T1) of short-lived radicals derived from the reactive residues. It will be shown how the analysis of the relaxation behavior opens the possibility of obtaining quantitative information about the correlation times of residue motion and characterizing the heterogeneity of the intramolecular dynamics of different residues in non-native states and the folding process.