Dibromothymoquinone (DBMIB) Replaces the Function of QA at 77 K in the Isolated Photosystem II Reaction Center (D1-D2-Cytochrome b559) Complex: Difference Spectrum of the P680+(DBMIB-) State

Transient absorbance changes of the primary electron donor chlorophyll a (P680) and acceptor pheophytin a (H) were measured at 77 K by nanosecond laser spectroscopy in the Dl-D2-cytochrome bSS9 photosystem II reaction center complex containing dibromomethylisopropyl benzoquinone (DBMIB). After the laser excitation of the reaction center in the presence of DBMIB, only the P680+(DBMIB) state was detected. P680+ mainly decayed with a t 1/e of 11 ms. In the absence of DBMIB, the excitation produced the P680+H~ radical pair. The radical pair produced the triplet state (P680T) with a t 1/e of 50 ns, and P680T then decayed with a tVt of 2.1 ms. It was concluded that H~ was oxidized by DBMIB in a time range faster than the detecting time resolution (3.5 ns) even at 77 K. The rapid oxidation of H~ by DBMIB was also confirmed by the suppression of delayed fluorescence with a decay t1/e of 50 ns. The P680+(DBMIB")/P680(DBMIB) difference spectrum exhibited a Q, band with a peak at 682 nm with a shoulder at 673 nm. The spectral shape was almost temperature insensitive between 77 and 265 K. The feature of this spectrum in the wavelength range between 330 and 720 nm was compared with that of P680 T/P680 or H"/H at 77 K.

[1]  A. Mulkidjanian,et al.  Photosystem II of green plants: topology of core pigments and redox cofactors as inferred from electrochromic difference spectra. , 1996, Biochemistry.

[2]  M. Groot,et al.  Subpicosecond Transient Absorption Difference Spectroscopy on the Reaction Center of Photosystem II: Radical Pair Formation at 77 K , 1995 .

[3]  E. Schlodder,et al.  Electron transfer reactions in Photosystem II core complexes from Synechococcus at low temperature — difference spectrum of P680+QA−P680 QA at 77 K , 1995 .

[4]  J. Dekker,et al.  Determination of the pigment stoichiometry of the photochemical reaction center of Photosystem II , 1995 .

[5]  R. Farid,et al.  Biological electron transfer , 1995, Journal of bioenergetics and biomembranes.

[6]  T. Tomo,et al.  15‐cis‐β‐Carotene found in the reaction center of spinach photosystem II , 1995 .

[7]  T. Tomo,et al.  15-CIS-β-CAROTENE FOUND IN THE REACTIONCENTER OF PHOTOSYSTEM II , 1995 .

[8]  J. Dekker,et al.  Site-Selection Spectroscopy of the Reaction Center Complex of Photosystem II. 1. Triplet-minus-Singlet Absorption Difference: Search for a Second Exciton Band of P-680 , 1994 .

[9]  E. Peterman,et al.  Temperature-dependent triplet and fluorescence quantum yields of the photosystem II reaction center described in a thermodynamic model. , 1994, Biophysical journal.

[10]  Y. Inoue,et al.  FT-IR studies on the triplet state of P680 in the photosystem II reaction center: triplet equilibrium within a chlorophyll dimer. , 1993, Biochemistry.

[11]  K. Satoh.  10 – Isolation and Properties of the Photosystem II Reaction Center , 1993 .

[12]  M. Seibert.  11 – Biochemical, Biophysical, and Structural Characterization of the Isolated Photosystem II Reaction Center Complex , 1993 .

[13]  P. Leeuwen,et al.  Analysis of the optical absorbance spectra of D1-D2-cytochrome b-559 complexes by absorbance-detected magnetic resonance: Structural properties of P680 , 1992 .

[14]  D. Klug,et al.  Observation of pheophytin reduction in photosystem two reaction centers using femtosecond transient absorption spectroscopy. , 1992, Biochemistry.

[15]  R. V. D. Vos,et al.  Steady state spectroscopy at 6 K of the isolated photosystem II reaction centre: Analysis of the red absorption band , 1992 .

[16]  M. Mimuro,et al.  Fluorescence of P700 and antenna chlorophylls in Photosystem I particles that contain 11 chlorophylls/P700 , 1992 .

[17]  S. Itoh,et al.  Artificial Quinones Replace the Function of Quinone Electron Acceptor (QA) in the Isolated D1-D2-Cytochrome b559 Photosystem II Reaction Center Complex , 1991 .

[18]  A. Rutherford,et al.  A chlorophyll tilted 30° relative to the membrane in the Photosystem II reaction centre , 1991 .

[19]  S. Fukuhara,et al.  Disintegration and reconstitution of photosystem II reaction center core complex. II, Possible involvement of low-molecular-mass proteins in the functioning of QA in the PS II reaction center , 1991 .

[20]  T. Aartsma,et al.  TIME-RESOLVED SPECTROSCOPY AT 10 K OF THE PHOTOSYSTEM II REACTION CENTER ;DECONVOLUTION OF THE RED ABSORPTION BAND , 1990 .

[21]  M. Seibert,et al.  Excited-state structure and energy-transfer dynamics of two different preparations of the reaction center of photosystem II: a hole-burning study , 1990 .

[22]  D. Klug,et al.  Thermodynamic properties of D1/D2/cytochrome b-559 reaction centres investigated by time-resolved fluorescence measurements , 1990 .

[23]  K. Satoh,et al.  Charge recombination between stabilized P-680+ and reduced cytochrome b-559 in quinone-reconstituted PS II reaction center , 1990 .

[24]  V. Shuvalov,et al.  Low temperature photochemistry and spectral properties of a photosystem 2 reaction center complex containing the proteins D1 and D2 and two hemes of Cyt b‐559 , 1989 .

[25]  H. Witt,et al.  Studies on the multiphasic charge recombination between chlorophyll aII+ (P-680+) and plastoquinone QA− in photosystem II complexes. Ultraviolet difference spectrum of Chl-aII+/Chl-aII , 1989 .

[26]  S. Itoh,et al.  Silicomolybdate substitutes for the function of a primary electron acceptor and stabilizes charge separation in the photosystem II reaction center complex , 1989 .

[27]  K. Satoh,et al.  Kinetic evidence for the function of Z in isolated photosystem II reaction centers , 1989 .

[28]  J. Barber,et al.  Evidence for the photo‐induced oxidation of the primary electron donor P680 in the isolated photosystem II reaction centre , 1989 .

[29]  J. Barber,et al.  Reconstitution of plastoquinone in the D1/D2/cytochrome b‐559 photosystem II reaction centre complex , 1988 .

[30]  S. Itoh,et al.  Delayed fluorescence in Photosystem I enhanced by phylloquinone (vitamin K-1) extraction with ether , 1988 .

[31]  I. Yamazaki,et al.  Dynamic fluorescence properties of D1-D2-cytochrome b-559 complex isolated from spinach chloroplasts: Analysis by means of the time-resolved fluoresence spectra in picosecond time range , 1988 .

[32]  J. Barber,et al.  Electron-transport properties of the isolated D1-D2-cytochrome b-559 Photosystem II reaction centre , 1988 .

[33]  J. Deisenhofer,et al.  Relevance of the photosynthetic reaction center from purple bacteria to the structure of photosystem II , 1988 .

[34]  O. Nanba,et al.  Isolation of a photosystem II reaction center consisting of D-1 and D-2 polypeptides and cytochrome b-559. , 1987, Proceedings of the National Academy of Sciences of the United States of America.