Abstract
Pulsed electron nuclear double resonance (ENDOR) spectroscopy at Q- and W-band frequencies was applied to single crystals of photosystem II from Th. elongatus. W-Band (1)H-ENDOR on the dark-stable radical state Y of the redox-active tyrosine residue Y(D) yields a complete mapping of the electronic structure of this amino acid radical in terms of an assignment of all hyperfine coupling tensors of the protons covalently bound to the side chain. This study can serve as a model case for the potential of high-field/high-frequency ENDOR on protein single crystals for obtaining highly resolved electronic structure information. Q-band (55)Mn-ENDOR was applied to the S(2) oxidation state of the water-splitting complex in photosystem II single crystals. Irrespective of the difficulties arising from the extremely broad electron paramagnetic resonance (EPR) spectroscopy ( approximately 200 mT) and ENDOR ( approximately 100 MHz) spectra a tentative assignment of the Mn ion in the formal oxidation state III to a Mn position in the structural model of PSII is possible on the basis of the ENDOR data.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
