Primary Processes in Photosynthesis: What do we learn from High-Field EPR Spectroscopy?

Möbius, K.; Savitsky, Anton; Fuchs, Martin

doi:10.1007/978-1-4757-4379-1_3

Cited by 9 publications

(2 citation statements)

References 98 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The W-band high-field EPR measurements presented in this paper were performed on a homebuilt W-band EPR spectrometer (3.4 T, 95 GHz, cw and pulsed mode), which was constructed in collaboration with Anton Savitsky and Klaus M6bius (Freie Universit/it Berlin) and built in our laboratory at the University of Osnabrª Figure 2 shows a block diagram of the heterodyne microwave bridge of the spectrometer according to the scheme published earlier for the setup in Berlin [11][12][13].…”

Section: W-band Epr Spectrometer Setupmentioning

confidence: 99%

High-field EPR and site-directed spin labeling reveal a periodical polarity profile: The sequence 88 to 94 of the phototransducer NpHtrII in complex with sensory rhodopsin, NpSRII

et al. 2006

View full text Add to dashboard Cite

Taking advantage of the improved spectral resolution of high-field electron paramagnetic resonance (EPR) at 95 GHz/3.4 Tas compared to conventional X-band EPR (9.5 GHz/0.34 T), detailed information on the polarity profile in a protein-protein interface is obtained. Nitroxide spin label side chains are introduced at positions 88 to 94 in the AS-1 sequence of the membrane adjacent HAMP domain of the transducer protein, NpHtrII, which is reconstituted in complex with sensory rhodopsin, NpSRII from Natronobacterium pharaonis. Position-dependent variations of the values of the nitroxide magnetic tensor components g.~, and A.: suggest that the spin label side chains at positions 88 to 93 of AS-1 are located between a hydrophobic anda hydrophilic microenvironment. The observed periodicity of the polarity properties of the respective spin label microenvironment agrees with an ~t-helical secondary structure of this part of AS-I and validates a recently published molecular model which locates residues 88 and 91 in the interface between helices F and G of NpSRII and AS-1 of NpHtrII close to the cytoplasmic lipid-water interface.

show abstract

Section: W-band Epr Spectrometer Setupmentioning

confidence: 99%

High-field EPR and site-directed spin labeling reveal a periodical polarity profile: The sequence 88 to 94 of the phototransducer NpHtrII in complex with sensory rhodopsin, NpSRII

et al. 2006

View full text Add to dashboard Cite

show abstract

“…Specifically, the increased spectral and also temporal resolution possible at 95 GHz/3.4 T and 360 GHz/12.8 T conditions, rendered possible a determination of light-induced electron-transfer in reaction centre proteins, and light-induced proton-pump intermediates from site-directed becteriorhodopsin proteins spin-labelled with nitroxides, and obtained from the purple membrane of halobacterium salinarium. 53 It has been suggested that chloride and formate anions interact competitively with the acceptor side of photosystem II, on the basis of ESR spectra. 54 Cadmium at a concentration range 7.5 to 75 mM was shown to result in a loss of pigments, reduction of thylakoids and decrease in oxygen evolution in leaves from chloroplasts in rice, while the degree of photosystem II reaction centre proteins and those from its light harvesting complex are not affected, indicating that cadmium does not adversely influence the structural organization of the photosystem.…”

Section: Biological Systemsmentioning

confidence: 99%