Pulsed electron-electron double resonance: Beyond distance measurements

PHYS 365

Olav Schiemann, o.schiemann@prisner.de1, Pavol Cekan, pavol@mi.is2, Dominik Margraf, Dominik@prisner.de1, Thomas F. Prisner, prisner@prisner.de1, and Snorri Th. Sigurdsson, snorrisi@hi.is2. (1) Institute of Physical and Theoretical Chemistry, Johann Wolfgang Goethe-University Frankfurt am Main, Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany, (2) Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavík, Iceland
Electron paramagnetic distance and orientation selective measurements on several double nitroxide-labeled shape-persistent DNA helixes were performed using Pulsed Electron-Electron Double resonance (PELDOR) on a commercial 9.7 GHz spectrometer. In addtion to the spin-spin distance measurements a systematic study of the PELDOR time domain signal as a function of the observer frequency with a constant pump pulse frequency disentangles constraints on the relative orientation of the two nitroxide spin moieties. Thus, the experiments not only yield the distance between the spin bearing groups, but also information about the relative orientation of the spin labels with respect to each other. This might allow investigation of tertiary and quarternary structural arrangements of biomolecules in more detail.
 

Physical Chemistry Poster Session
7:00 PM-9:00 PM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Physical Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007