A difference Fourier transform infrared spectroscopic study of chlorophyll oxidation in hydroxylamine-treated photosystem II.
In oxygenic photosynthesis, photosystem II is the chlorophyll-containing reaction center that carries out the light-induced transfer of electrons from water to plastoquinone. Fourier transform infrared spectroscopy can be used to obtain information about the structural changes that accompany electron transfer in photosystem II. The vibrational difference spectrum associated with the reduction of photosystem II acceptor quinones is of interest. Previously, a high concentration of the photosystem II donor, hydroxylamine, has been used to obtain a spectrum attributed to QA- -QA (Berthomieu, C., Nabedryk, E., Mantele, W. and Breton, J. FEBS Lett. (1990) 269, 363). Here, we use electron paramagnetic resonance, Fourier transform infrared spectroscopy, and 15N isotopic labeling to show that the difference infrared spectrum, obtained under these conditions, also exhibits a contribution from the oxidation of chlorophyll.
MacDonald
G M
GM
Department of Biochemistry, University of Minnesota, St. Paul 55108, USA.
Steenhuis
J J
JJ
Barry
B A
BA
D002734:Chlorophyll / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D019811:Hydroxylamine; D006898:Hydroxylamines / Q000494:pharmacology*; D045342:Light-Harvesting Protein Complexes; D009587:Nitrogen Isotopes; D010084:Oxidation-Reduction; D045322:Photosynthetic Reaction Center Complex Proteins / Q000187:drug effects* / Q000378:metabolism; D045332:Photosystem II Protein Complex; D017550:Spectroscopy, Fourier Transform Infrared
D006898:Hydroxylamines; D045342:Light-Harvesting Protein Complexes; D009587:Nitrogen Isotopes; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D002734:Chlorophyll; D019811:Hydroxylamine