Rhodopseudomonas viridis photosynthetic reaction

Figure 12.15 Schematic arrangement of the photosynthetic pigments in the reaction center of Rhodopseudomonas viridis. The twofold symmetry axis that relates the L and the M subunits is aligned vertically in the plane of the paper. Electron transfer proceeds preferentially along the branch to the right. The periplasmic side of the membrane is near the top, and the cytoplasmic side is near the bottom of the structure. (From B. Furugren, courtesy of the Royal Swedish Academy of Science.)...

Deisenhofer, J., Michael, H. Nobel lecture. The photosynthetic reaction center from the purple bacterium Rhodopseudomonas viridis. EMBO f. 8 2149-2169, 1989. 

Deisenhofer, J., et al. Structure of the protein subunits in the photosynthetic reaction center of Rhodopseudomonas viridis at 3 A resolution. Nature 318 618-624, 1985. 

Michel, H. Three-dimensional crystals of a membrane protein complex. The photosynthetic reaction center from Rhodopseudomonas viridis.. Mol. Biol. 

Michel, H., et al. The "heavy" subunit of the photosynthetic reaction center from Rhodopseudomonas viridis isolation of the gene, nucleotide and amino acid sequence. EMBO J. 4 1667-1672, 1985. 

What molecular architecture couples the absorption of light energy to rapid electron-transfer events, in turn coupling these e transfers to proton translocations so that ATP synthesis is possible Part of the answer to this question lies in the membrane-associated nature of the photosystems. Membrane proteins have been difficult to study due to their insolubility in the usual aqueous solvents employed in protein biochemistry. A major breakthrough occurred in 1984 when Johann Deisenhofer, Hartmut Michel, and Robert Huber reported the first X-ray crystallographic analysis of a membrane protein. To the great benefit of photosynthesis research, this protein was the reaction center from the photosynthetic purple bacterium Rhodopseudomonas viridis. This research earned these three scientists the 1984 Nobel Prize in chemistry. 

It is interesting to compare the thermal-treatment effect on the secondary structure of two proteins, namely, bacteriorhodopsin (BR) and photosynthetic reaction centers from Rhodopseudomonas viridis (RC). The investigation was done for three types of samples for each object-solution, LB film, and self-assembled film. Both proteins are membrane ones and are objects of numerous studies, for they play a key role in photosynthesis, providing a light-induced charge transfer through membranes—electrons in the case of RC and protons in the case of BR. 

Thompson MA, Zemer MC (1991) A theoretical examination of the electronic structure and spectroscopy of the photosynthetic reaction center from Rhodopseudomonas viridis. J Am Chem Soc 113 8210-8215... 

Until a recent x-ray diffraction study (17) provided direct evidence of the arrangement of the pigment species in the reaction center of the photosynthetic bacterium Rhodopseudomonas Viridis, a considerable amount of all evidence pertaining to the internal molecular architecture of plant or bacterial reaction centers was inferred from the results of in vitro spectroscopic experiments and from work on model systems (5, 18, 19). Aside from their use as indirect probes of the structure and function of plant and bacterial reaction centers, model studies have also provided insights into the development of potential biomimetic solar energy conversion systems. In this regard, the work of Netzel and co-workers (20-22) is particularly noteworthy, and in addition, is quite relevant to the material discussed at this conference. 

Figure 6.2. (a) Photosynthetic reaction center of Rhodopseudomonas viridis Reprinted from the Protein Data Bank, H. M. Berman, J. Westbrook, Z. Feng, G. Gilliland, T. N. Bhat, H. Weissig, I. N. Shindyalov, P. E. Bourne, Nucleic Acids Res. 2000, 1, 235 (http // www.pdb.org/) PDB ID IDXR, C. R. D. Lancaster, M. Bibikova, P. Sabatino, D. Oesterhelt, H. Michel, J. Biol Chem. 2000, 275, 39364. (b) arrangement of the essential components in the purple bacterium Rh. sphaeroides. [Adapted from Ref. 5.]... 

Figure 23-31 (A) Stereoscopic ribbon drawing of the photosynthetic reaction center proteins of Rhodopseudomonas viridis. Bound chromophores are drawn as wire models. The H subunit is at the bottom the L and M subunits are in the center. The upper globule is the cytochrome c. The view is toward the flat side of the L, M module with the L subunit toward the observer. (B) Stereo view of only the bound chromophores. The four heme groups Hel-He4, the bacteriochlorophylls (Bchl) and bacteriopheophytins (BPh), the quinones QA and QB/ and iron (Fe) are shown. The four hemes of the cytochrome are not shown in...

J. Hasegawa and H. Nakatsuji, Mechanism and unidirectionality of the electron transfer in the photosynthetic reaction center of Rhodopseudomonas Viridis SAC-CI theoretical study, J. Phys. Chem. B, 102 (1998) 10420-10430. 

Thomson, M.A. and Schenter G.K., Excited States of the Bacteriochlorophyll b Dimer of Rhodopseudomonas viridis A QM/MM Study of the Photosynthetic Reaction Center That Includes MM Polarization. J. Phys. Chem. (1995) 99 6374-386. 

Figure 4-7. Electronic factors in the rate constant calculated for the electron transfers in the bacterial photosynthetic reaction centers of (a) Rhodopseudomonas viridis, and (b) Rhodobactor sphaeroides...

See, e.g., J. Deisenhofer, H. Michel, The Photosynthetic Reaction Center from the Purple Bacterium Rhodopseudomonas-Viridis. Science 1989, 245, 1463-1473 M. E. Michel-Beyerle, M. Plato, J. Deisenhofer, H. Michel, M. Bixton, J. Jortner, Unidirectionality of Charge Separation in Reaction Centers of Photosynthetic Bacteria. Biochim. Biophys. Acta 1988, 932, 52-70. 

The Nobel Prize in chemistry was awarded to Johan Deisenhofer, Robert Huber, and Hartmut Michel in 1988 for unraveling the structure of the reaction center from the purple photosynthetic bacterium Rhodopseudomonas viridis using X-ray crystallography. 

Meyer, T. E., Bartsch, R. G., Cusanovich, M. A., and Tollin, G., 1993, Kinetics of photooxidation of soluble cytochromes, hipip, and azurin by the photosynthetic reaction center of the purple phototrophic bacterium Rhodopseudomonas viridis Biochemistry 32 471994726. 

Michel, H., Deisenhofer, J., and Epp, O., 1986, Pigment protein interactions in the photosynthetic reaction center from Rhodopseudomonas viridis Embo J. 5 244592451. 

Deisenhofer, J., Epp, O., Sinning, I., and Michel, H., 1995, Crystallographic refinement at 2.3 resolution and refined model of the photosynthetic reaction centre from Rhodopseudomonas viridis. J. Mol. Biol., 246 4299457. 

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