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Title: Spectroscopic properties of photosystem II reaction center revisited

 [1];  [2];  [3];  [1]
  1. Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius, Lithuania, Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Sauletekio 3, 10257 Vilnius, Lithuania
  2. Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius, Lithuania
  3. Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA
Publication Date:
Sponsoring Org.:
OSTI Identifier:
Grant/Contract Number:
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 147; Journal Issue: 11; Related Information: CHORUS Timestamp: 2018-02-14 20:07:03; Journal ID: ISSN 0021-9606
American Institute of Physics
Country of Publication:
United States

Citation Formats

Gelzinis, Andrius, Abramavicius, Darius, Ogilvie, Jennifer P., and Valkunas, Leonas. Spectroscopic properties of photosystem II reaction center revisited. United States: N. p., 2017. Web. doi:10.1063/1.4997527.
Gelzinis, Andrius, Abramavicius, Darius, Ogilvie, Jennifer P., & Valkunas, Leonas. Spectroscopic properties of photosystem II reaction center revisited. United States. doi:10.1063/1.4997527.
Gelzinis, Andrius, Abramavicius, Darius, Ogilvie, Jennifer P., and Valkunas, Leonas. 2017. "Spectroscopic properties of photosystem II reaction center revisited". United States. doi:10.1063/1.4997527.
title = {Spectroscopic properties of photosystem II reaction center revisited},
author = {Gelzinis, Andrius and Abramavicius, Darius and Ogilvie, Jennifer P. and Valkunas, Leonas},
abstractNote = {},
doi = {10.1063/1.4997527},
journal = {Journal of Chemical Physics},
number = 11,
volume = 147,
place = {United States},
year = 2017,
month = 9

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on September 21, 2018
Publisher's Accepted Manuscript

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Cited by: 1work
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  • Photosystem II reaction center (RC) preparations isolated from spinach (Spinacea oleracea) by the Nanba-Satoh procedure are quite labile, even at 4{degree}C in the dark. Simple spectroscopic criteria were developed to characterize the native state of the material. Degradation of the RC results in (a) blue-shifting of the red-most absorption maximum, (b) a shift of the 77 K fluorescence maximum from {approximately}682 nm to {approximately}670 nm, and (c) a shift of fluorescence lifetime components from 1.3-4 nanoseconds and >25 nanoseconds to {approximately}6-7 nanoseconds. Fluorescence properties at 77 K seem to be a more sensitive spectral indicator of the integrity of themore » material. The >25 nanosecond lifetime component is assigned to P680{sup +} Phenophytin{sup -}recombination luminescence, which suggest a correlation between the observed spectral shifts and the photochemical competence of the preparation. Substitution of lauryl maltoside for Triton X-100 immediately after RC isolation stabilizes the RCs and suggests that Triton may be responsible for the instability.« less
  • The authors report the results of a Moessbauer study of the low-potential iron-sulfur cluster F{sub X} in the Photosystem I core protein of Synechococcus 6301. The Moessbauer spectrum of F{sub X} in the oxidized state shows an isomer shift of 0.42 mm/s, which is in good agreement with the 0.43 mm/s isomer shift found in (4Fe-4S) proteins but not with the isomer shift of 0.26 mm/s found in (2Fe-2S) proteins. In the reduced state the spectrum is asymmetrically broadened at 80 K, indicating the presence of two very closely spaced doublets with an average isomer shift of 0.55 mm/s, whichmore » is also in agreement with (4Fe-4S) proteins. At 4.2 K, the spectrum exhibits broadening and magnetic splitting similar to what is observed for (4Fe-4S) proteins and quite unlike (2Fe-2S) proteins. Given the assumption that the iron atoms of F{sub X} are tetrahedrally coordinated with sulfur ligands, the data strongly support the assignment of F{sub X} as a (4Fe-4S) cluster.« less
  • Resonance Raman and subpicosecond resolution transient absorption data are presented on the reaction center (RC) from the Rb. sphaeroides (M)H202L/(L)L131H double mutant. This RC contains a bacteriochlorophyll/bacteriopheophytin heterodimer primary electron donor (D), as a result of introducing a Leu at M subunit residue 202, as well as a hydrogen bond to the ring-V keto group of he BChl component, as a result of introducing a His at L subunit residue 131. The double mutant shows a longer lifetime (40ps) for the lowest excited singlet state and a lower quantum yield of change separation (25%) than observed perviously for the heterodimermore » single mutants (M)H202L and (L)H173L. These changes are ascribed in large measure to a decrease in the contribution of the accessory pigment BChl{sub L} to the initial stage of charge separation. Both the rate of internal conversion of the excited primary donor and the characteristics of the near-infrared ground state absoption of the dimer appear to be intermediate between those found for the (M)H202L single mutant and wild type RCs. Resonance Raman profiles obtained via excitation at several wavelengths across the heterodimer absorption band suggest that there is a change in the nature and perhaps ordering of the two lowest excited states of the heterodimer in the double mutant compared with the single mutant. 44 refs., 13 figs., 1 tab.« less
  • The rate of the electron transfer reaction from the reduced primary electron acceptor chlorophyll a (A{sub 0}{sup -}) to the secondary acceptor quinone (Q) was measured by picosecond-nanosecond laser spectroscopy at 280 K in the photosynthetic reaction center (RC) complex of plant photosystem I (PS I). The free energy change ({Delta}G{sub 0}) of the reaction was varied between -1.1 and +0.2 eV by the reconstitution of 13 different quinone/quinonoid compounds after the extraction of the intrinsic phylloquinone. Phylloquinone and its natural analog menaquinone, both of which show a {Delta}G{sup 0} value of -0.34 eV, gave the highest rate constant (k)more » of (23 ps){sup -1}. Analysis of log k versus {Delta}G{sup 0} plot according to the quantum mechanical electron transfer theory gave the total reorganization energy ({lambda}{sub total}) of 0.30 eV and the electronic coupling (V) of 14 cm{sup -1}. The natural system is shown to be highly optimized to give a {Delta}G{sup 0} = -{lambda}{sub total} condition. The {lambda}{sub total} value is smaller and the V value is larger than those estimated in the corresponding reaction between the reduced primary acceptor bacteriopheophytin (H{sup -}) and the secondary acceptor ubiquinone (Q{sub A}) in the purple bacterial RC complex. It is concluded that the A{sub 0}{sup -}Q {yields} A{sub 0}Q{sup -} reaction in the PS I RC occurs in protein environments, which give a low dielectric property, with a shorter electron transfer distance compared to the reaction between H and Q{sub A}. 46 refs., 7 figs., 2 tabs.« less
  • Rates of sequential electron transfer reactions from the primary electron donor chlorophyll dimer (P700) to the electron acceptor chlorophyll a-686 (A[sub 0]) and to the secondary acceptor quinone (Q[sub [phi]]) are measured by picosecond absorption spectroscopy in spinach photosystem I (PS I) particles. In the particles, 85-90% of antenna chlorophylls are extracted and the intrinsic phylloquinone (Q[sub [phi]]) is removed and replaced by different quinones. (1) The excited single state of P700, monitored by the absorbance change at 695 nm, appeared with a time constant shorter than 1 ps after excitation with a 605 nm, 1 ps pulse at anmore » intensity of 0.8 or 1.5 photons/reaction center. Indication for the absorbance change of the chlorophylls, which may function as the intermediate electron acceptor between P700 and A[sub 0] or between A[sub 0] and Q[sub [phi]], was not obtained. 45 refs., 5 figs., 1 tab.« less