Hostname: page-component-745bb68f8f-hvd4g Total loading time: 0 Render date: 2025-01-30T19:13:07.505Z Has data issue: false hasContentIssue false
  • English
  • Français

Primary photochemical reactions in chloroplast photosynthesis

Published online by Cambridge University Press:  17 March 2009

Alan J. Bearden  and
Richard Malkin
Alan J. Bearden
Affiliation:
Donner Laboratory
Richard Malkin
Affiliation:
Department of Cell Physiology, University of California, Berkeley, California 94720 (U.S.A.)
Get access Rights & Permissions [Opens in a new window]

Extract

Photosynthesis begins with the absorption of light energy and this absorbed energy is transferred to special sites, termed reaction centres. At these sites, the light energy is transformed into chemical products through an oxidation-reduction reaction that generates the primary reactants, an oxidized pigment molecule (P+) and a reduced electron acceptor (A–) (Clayton, 1972). The subsequent reactions of these species in the dark ultimately results in the formation of chemical products required for the fixation of CO2. In this essay we will discuss the nature of the primary reactants generated in the light reactions of chloroplast photosynthesis, stressing recent advances in the identification and characterization of such reactants.

Type
Research Article
Information
Quarterly Reviews of Biophysics , Volume 7 , Issue 2 , May 1974 , pp. 131 - 177
Copyright
Copyright © Cambridge University Press 1974

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Amesz, J. (1973). The function of plastoquinone in photosynthetic electron transport. Biochim. biophys. Acta 301, 35–51.CrossRefGoogle ScholarPubMed
Arnon, D. I. (1965 a). Ferredoxin and photosynthesis. Science, N.Y. 149, 1460–9.CrossRefGoogle ScholarPubMed
Arnon, D. I. (1965 b). Role of ferredoxin in plant and bacterial photosynthesis. In Non-Heme Iron Proteins: Role in Energy Conversion (ed. Pietro, A. San), Pp. 137–73. Yellow Springs, Ohio: Antioch Press.Google Scholar
Babcock, G. T. (1973). Kinetics and intermediates in photosynthetic oxygen evolution. Ph.D. thesis, University of California, Berkeley.Google Scholar
Baker, R. A. & Weaver, E. C. (1973). A correlation of EPR spins with P700 in spinach chloroplasts. Photochem & Photobiol. 18, 237–44.CrossRefGoogle Scholar
Bearden, A. J. & Dunham, W. R. (1970). Iron electronic configurations in proteins. Struct. & Bond. 8, 1–52.CrossRefGoogle Scholar
Bearden, A. J. & Malkin, R. (1972 a). The bound ferredoxin of chloroplasts: A role as the primary electron acceptor of Photosystem I. Biochem. biophys. Res. Commun. 46, 1299–305.CrossRefGoogle ScholarPubMed
Bearden, A. J. & Malkin, R. (1972 b). Quantitative EPR studies of the primary reaction of Photosystem I in chloroplasts. Biochim. biophys. Acta 283, 456–68.CrossRefGoogle ScholarPubMed
Bearden, A. J. & Malkin, R. (1973). Oxidation-reduction potential dependence of low-temperature photoreactions of chloroplast Photo-system II. Biochim. biophys. Acta 325, 266–74.CrossRefGoogle Scholar
Beinert, H. & Kok, B. (1964). An attempt at quantitation of the sharp light-induced electron paramagnetic resonance signal in photosynthetic materials. Biochim. biophys. Acta 88, 278–88.Google ScholarPubMed
Beinert, H., Kok, B. & Hoch, G. (1962). The light-induced electron paramagnetic resonance signal of photocatalyst P700. Biochem. biophys. Res. Commun. 7, 209–12.CrossRefGoogle ScholarPubMed
Bendall, D. S. (1968). Oxidation-reduction potentials of cytochromes in chloroplasts from higher plants. Biochem. J. 109, 46P.CrossRefGoogle ScholarPubMed
Bishop, N. I. (1971). Photosynthesis: The electron transport system of green plants. A. Rev. Biochem. 40, 197–226.CrossRefGoogle ScholarPubMed
Black, C. C. Jr. (1966). Chloroplast reactions with dipyridyl salts. Biochim. biophys. Acta 120, 332–40.CrossRefGoogle ScholarPubMed
Boardman, N. K. (1968). The photochemical systems of photosynthesis. Adv. Enzymol. 30, 1–79.Google ScholarPubMed
Boardman, N. K. (1970). Physical separation of the photosynthetic photochemical systems. A. Rev. Pl. Physiol. 21, 115–40.CrossRefGoogle Scholar
Boardman, N. K. (1971). Subchloroplast fragments: Digitonin method. Meth. Enym. 23, 268–76.Google Scholar
Boardman, N. K., Anderson, J. M. & Hiller, R. G. (1971). Photooxidation of cytochromes in leaves and chloroplasts at liquid-nitrogen temperature. Biochim. biophys. Acta 234, 126–36.CrossRefGoogle ScholarPubMed
Borg, D. C., Fajer, J., Felton, R. H. & Dolphin, D. (1970). The II-cation radical of chlorophyll a. Proc. natn. Acad. Sci. U.S.A. 67 813–20.CrossRefGoogle Scholar
Butler, W. L. (1962). Effects of red and far-red light on the fluorescence yield of chlorophyll in vivo. Biochim. biophys. Acta 64, 309–57.CrossRefGoogle ScholarPubMed
Butler, W. L. (1972 a). The relationship between P-680 and C-550. Biophys. J. 12, 851–7.CrossRefGoogle ScholarPubMed
Butler, W. L. (1972 b). On the primary nature of fluorescence yield changes associated with photosynthesis. Proc. natn. Acad. Sci. U.S.A. 69, 3420–2.CrossRefGoogle Scholar
Butler, W. L. (1973). Primary photochemistry of Photosystem II of photosynthesis. Accounts Chem. Res. 6, 177–84.CrossRefGoogle Scholar
Butler, W. L. & Okayama, S. (1971). The photoreduction of C-550 in chloroplasts and its inhibition by lipase. Biochim. biophys. Acta 245, 237–9.CrossRefGoogle ScholarPubMed
Butler, W. L., Visser, J. W. M. & Simons, H. L. (1973). The kinetics of light-induced changes of C-500, cytochrome b 559 and fluorescence yield in chloroplasts at low temperature. Biochim. biopizys. Acta 292, 140–51.CrossRefGoogle Scholar
Calvin, M. (1961). Some photochemical and photophysical reactions of chlorophyll and its relatives. In Light and Life (ed. McElroy, W. D. and Glass, B.), pp. 317–55. Baltimore: Johns Hopkins Press.Google Scholar
Calvin, M. & Androes, G. M. (1962). Primary quantum conversion in photosynthesis. Science, N.Y. 138, 867–73.CrossRefGoogle ScholarPubMed
Calvin, M. & Bassham, J. A. (1962). The Photosynthesis of Carbon Compounds. New York: Benjamin.Google Scholar
Chance, B. & Bonner, W. D. Jr. (1963). The temperature insensitive oxidation of cytochrome f in green leaves - a primary biochemical event of photosynthesis. In Photosynthetic Mechanisms of Green Plants (ed. Kok, B. and Jagendorf, A. T.), pp. 66–81. Washington, D.C.: National Academy of Sciences-National Research Council.Google Scholar
Chance, B., Kihara, T., Devault, D., Hildreth, W., Nishimura, M. & Hiyama, T. (1969). Temperature-insensitive electron transfer in photosynthetic systems. In Progress in Photosynthesis Research (ed. Metzner, H.), pp. 1321–46. Tübingen: Laupp.Google Scholar
Chance, B., San, Pietro A., Avron, M. & Hildreth, W. W. (1965). The role of spinach ferredoxin (PPNR) in photosynthetic electron transfer. In Non-Heme Iron Proteins: Role in Energy Conversion (ed. Pietro, A. San), pp. 225–36. Yellow Springs, Ohio: Antioch Press.Google Scholar
Cheniae, G. M. (1970). Photosystem II and O2 evolution. A. Rev. Pl. Physiol. 21, 467–98.CrossRefGoogle Scholar
Clayton, R. K. (1971). Photochemical reaction centers and photosynthetic membranes. Adv. chem. Phys. 19, 353–78.CrossRefGoogle Scholar
Clayton, R. K. (1972). Physical mechanisms in photosynthesis: Past elucidations and current problems. Proc. natn. Acad. Sci. U.S.A. 69 44–9.CrossRefGoogle ScholarPubMed
Clayton, R. K. (1973). Primary processes in bacterial photosynthesis. A. Rev. Biophys. Bioeng. 2, 131–56.CrossRefGoogle ScholarPubMed
Commoner, B., Heise, J. J., Lippincott, B. B., Norberg, R. E., Passonneau, J. V. & Townsend, J. (1957). Biological activity of free radicals. Science, N.Y. 126, 57–63.CrossRefGoogle ScholarPubMed
Commoner, B., Heise, J. J. & Townsend, J. (1956). Light-induced paramagnetism in chloroplasts. Proc. natn. Acad. Sci. U.S.A. 42, 710–18.CrossRefGoogle ScholarPubMed
Cox, R. P. & Bendall, D. S. (1972). The effects on cytochrome b559 (HP) and P546 of treatments that inhibit oxygen evolution by chloroplasts. Biochim. biophys. Acta 283, 124–35.CrossRefGoogle Scholar
Cramer, W. A. & Butler, W. L. (1969). Potentiometric titration of the fluorescence yield of spinach chloroplasts. Biochim. biophys. Acta 172, 503–10.CrossRefGoogle ScholarPubMed
Dietrich, W. E. Jr, & Thornber, J. P. (1971). The P700-chlorophyll a protein of a blue-green alga. Biochim. biophys. Acta 245, 482–93.CrossRefGoogle Scholar
Döring, G., Renger, G., Vater, J. & Witt, H. T. (1969). Properties of the photoactive chlorophyll aII in photosynthesis. Z. Naturf. B 24, 1139–43.CrossRefGoogle ScholarPubMed
Döring, G., Stiehl, H. H. & Witt, H. T. (1967). A second chlorophyll reaction in the electron chain of photosynthesis – registration by the repetitive excitation technique. Z. Naturf. B 22, 639–44.CrossRefGoogle ScholarPubMed
Döring, G. & Witt, H. T. (1972). The photoactive chlorophyll aII in photosynthesis. In Proc. 2nd Int. Congr. on Photosynthesis Res. (ed. Forti, G., Avron, M. and Melandri, A.), pp. 39–45. The Hague: Junk.Google Scholar
Dutton, P. L. & Leigh, J. S. Jr, (1973). Electron spin resonance characterization of Chromatium D hemes, non-heme irons and the components involved in primary photochemistry. Biochim. biophys. Acta 314, 178–90.CrossRefGoogle ScholarPubMed
Dutton, P. L., Leigh, J. S. Jr, & Reed, D. W. (1973). Primary events in the photosynthetic reaction centre from Rhodopseudomonas spheroides strain R26: Triplet and oxidized states of bacteriochiorophyll and the identification of the primary acceptor. Biochim. biophys. Acta 292, 654–64.CrossRefGoogle Scholar
Duysens, L. N. M. (1964). Photosynthesis. Prog. Biophys. Mol. Biol. 14, 1–104.CrossRefGoogle Scholar
Duysens, L. N. M. & Sweers, H. E. (1963). Mechanism of two photo-chemical reactions in algae as studied by means of fluorescence. In Studies on Microalgae and Photosynthetic Bacteria (ed. Japan. Soc. Plant Physiol.), pp. 353–72. Tokyo: University of Tokyo Press.Google Scholar
Evans, M. C. W., Reeves, S. G. & Telfer, A. (1973). The detection of a bound ferredoxin in the photosynthetic lamellae of blue-green algae and other oxygen-evolving photosynthetic organisms. Biochem. biophys. Res. Commun.. 51, 593–6.CrossRefGoogle ScholarPubMed
Evans, M. C. W., Telfer, A. & Lord, A. V. (1972). Evidence for the role of a bound ferredoxin as the primary electron acceptor of Photosystem I in spinach chloroplasts. Biochim. biophys. Acta 267, 530–7.CrossRefGoogle ScholarPubMed
Erixon, K. & Butler, W. L. (1971 a). Light-induced absorbance changes in chloroplasts at –196 °C. Photochem. & Photobiol. 14, 427–33.CrossRefGoogle Scholar
Erixon, K. & Butler, W. L. (1971 b). The relationship between Q, C-550 and cytochrome b559 in photoreactions at –196 °C in chloroplasts. Biochim. biophys. Acta 234, 381–9.CrossRefGoogle Scholar
Floyd, R. A., Chance, B. & Devault, D. (1971). Low-temperature photo- induced reactions in green leaves and chloroplasts. Biochim. biophys. Acta 226, 103–12.CrossRefGoogle ScholarPubMed
Forbush, B. & Kok, B. (1968). Reaction between primary and secondary electron acceptors of Photosystem II of photosynthesis. Biochim. biophys. Acta 162, 243–53.CrossRefGoogle ScholarPubMed
Fujita, Y. & Myers, J. (1965 a). Light-induced redox reactions of cytochrome c by cell-free preparation of Anabaena cylindrica. Biochem. biophys. Res. Commun. 19, 604–8.CrossRefGoogle ScholarPubMed
Fujita, Y. & Myers, J. (1965 b). Light-induced cytochrome c redox reactions by a cell-free preparation of Anabaena cylindrica. Archs Biochem. Biophys. 112, 519–23.CrossRefGoogle ScholarPubMed
Fuller, R. C. & Nugent, N. A. (1969). Pteridines and the function of the photosynthetic reaction center. Proc. natn. Acad. Sci. U.S.A. 63, 1311–18.CrossRefGoogle ScholarPubMed
Govindjee, , Ichimura, S., Cedaratand, C. & Rabinowitch, E. (1960). Effect of combining far-red light with shorter wave light on the excitation of fluorescence in Chiorella. Archs Biochem. Biophys. 89, 322–3.CrossRefGoogle Scholar
Hiller, R. G., Anderson, J. M. & Boardman, N. K. (1971). Photooxidation of cytochrome b 559 in leaves and chioroplasts at room temperature. Biochim. biophys. Acta 245, 439–52.CrossRefGoogle Scholar
Hind, G. & Olson, J. M. (1968). Electron transport pathways in photosynthesis. A. Rev. Pl. Physiol. 19, 249–82.CrossRefGoogle Scholar
Hiya, T. & Ke, B. (1971 a). A new photosynthetic pigment ‘P430’: Its possible role as the primary electron acceptor of Photosystem I. Proc. natn. Acad. Sd. U.S.A. 68, 1010–13.CrossRefGoogle Scholar
Hiyama, T. & Ke, B. (1971 b). A further study of P430: A possible primary electron acceptor of Photosystem I. Archs Biochem. Biophys. 147, 99–108.CrossRefGoogle ScholarPubMed
Hiyama, T. & Ke, B. (1972). Difference spectra and extinction coefficients of P700. Biochim. biophys. Acta 267, 160–71.CrossRefGoogle Scholar
Joliot, P. & Joliot, A. (1972). Studies on the quenching properties of the Photosystem II electron acceptor. In Proc. 2nd Int. Congr. on Photosynthesis Res. (ed. Forti, G., Avron, M. and Melandri, A.), pp. 26–38. The Hague: Junk.Google Scholar
Joliot, P. & Joliot, A. (1973). Different types of quenching involved in Photosystem II centers. Biochim. biophys. Acta 305, 302–16.CrossRefGoogle ScholarPubMed
Kamen, M. D. (1961). Comments on the function of haem proteins as related to primary photochemical processes in photosynthesis. In Light and Life (ed. McElroy, W. D. and Glass, B.), pp. 483–8. Baltimore: Johns Hopkins.Google Scholar
Kamen, M. D. (1963). Primary Processes in Photosynthesis. New York: Academic Press.Google Scholar
Kassner, R. J. & Kamen, M. D. (1967). The photoreduction of spinach ferredoxin in the presence of porphryin and an electron donor. Proc. natn. Acad. Sd. U.S.A. 58, 2445–50.CrossRefGoogle Scholar
Kassner, R. J. & Kamen, M. D. (1968). Zn-coproporphryin catalyzed photo- reduction of spinach ferredoxin. Biochem. biophys. Res. Commun. 32, 782–7.CrossRefGoogle Scholar
Katz, E. (1949). Photosynthesis in Plants, pp. 287–92. Ames: Iowa State College Press.Google Scholar
Katz, J. J. & Norris, J. R. Jr (1973). Chlorophyll and light energy transduction in photosynthesis. Curr. Top. Bioenerg. 5, 41–75.CrossRefGoogle Scholar
Ke, B. (1972). The rise time of photoreduction, difference spectrum, and oxidation-reduction potential of P430. Archs Biochem. Biophys. 152, 70–7.Google ScholarPubMed
Ke, B. (1973). The primary electron acceptor of Photosystem I. Biochim. biophys. Acta 301, 1–33.CrossRefGoogle ScholarPubMed
Ke, B. & Beinert, H. (1973). Evidence for the identity of P430 of Photo-system I and chioroplast-bound iron–sulfur protein.of Photosystem I. Biochim. biophys. Acad 305, 689–93.CrossRefGoogle Scholar
Ke, B., Hansen, R. E. & Beinert, H. (1973). Oxidation-reduction potentials of bound iron–sulfur proteins of Photosystem I. Proc. natn. Acad. Sci. U.S.A. 70, 2941–5.CrossRefGoogle ScholarPubMed
Ke, B., Ogawa, T., Hiyama, T. & Vernon, L. P. (1971). Experimental determination of the molar differential extinction coefficient of P700. Biochim. biophys. Acta 226, 53–62.CrossRefGoogle ScholarPubMed
Knaff, D. B. & Arnon, D. I. (1969 a). Spectral evidence for a new photo- reactive component of the oxygen-evolving system in photosynthesis. Proc. natn. Acad. Sci. U.S.A. 63, 963–9.CrossRefGoogle Scholar
Knaff, D. B. & Arnon, D. I. (1969 b). A concept of three light reactions in photosynthesis by green plants. Proc. natn. Acad. Sci. U.S.A. 64, 715–22.CrossRefGoogle ScholarPubMed
Knaff, D. B. & Arnon, D. I. (1969 c). Light-induced oxidation of a chioroplast b-type cytochrome at –189 °C. Proc. natn. Acad. Sci. U.S.A. 63, 956–62.CrossRefGoogle Scholar
Knaff, D. B. & Arnon, D. I. (1971). On two photoreactions in system II of ant photosynthesis. Biochim. biophys. Acta 226, 400–8.CrossRefGoogle Scholar
Knaff, D. B. & Malkin, R. (1973). The oxidation-reduction potentials of electron carriers in chloroplast Photosystem I fragments. Archs Biochem. Biophys. 159, 555–62.CrossRefGoogle ScholarPubMed
Kohl, D. H. (1972). Photosynthesis. In Biological Applications of Electron Spin Resonance (ed. Swartz, H. M., Bolton, J. R. and Borg, D. C.), pp. 213– 64. New York: Wiley-Interscience.Google Scholar
Kok, B. (1956). On the reversible absorption change at 705 mμ in photosynthetic organisms. Biochim. biophys. Acta 22, 399–401.CrossRefGoogle Scholar
Kok, B. (1957). Absorption changes induced by the photochemical reaction of photosynthesis. Nature, Lond. 179, 583–4.CrossRefGoogle Scholar
Kok, B. (1961). Partial purification and determination of oxidation reduction potential of the photosynthetic chlorophyll complex absorbing at 700 mμ. Biochim. biophys. Acta 48, 527–33.CrossRefGoogle Scholar
Kok, B. (1963). Fluorescence studies. In Photosynthetic Mechanisms of Green Plants (ed. Kok, B. and Jagendorf, A. T.), pp. 45–55. Washington, D.C.: National Academy of Sciences–National Research Council.Google Scholar
Kok, B. & Hoch, G. (1961). Spectral changes in photosynthesis. Light and Life (ed. McElroy, W. D. and Glass, B.), pp. 397–423. Baltimore: Johns Hopkins.Google Scholar
Kok, B., Malkin, S., Owens, O. & Forbush, B. (1966). Observations on the reducing side of Photosystem II. Brookhaven Symp. Biol. 19, 446–59.Google Scholar
Kok, B., Rurainski, H. J. & Owen, O. V. H. (1965). The reducing power generated in Photoact I of photosynthesis. Biochim. biophys. Acta 109, 347–56.CrossRefGoogle ScholarPubMed
Leigh, J. S. Jr, & Dutton, P. L. (1972). The primary electron acceptor in photosynthesis. Biochem. biophys. Res. Commun. 46, 414–21.CrossRefGoogle ScholarPubMed
Loach, P. & Katz, J. J. (1973). Primary photochemistry of photosynthesis. Photochem. & Photobiol. 17, 195–208.CrossRefGoogle Scholar
Lozier, R. H. & Butler, W. L. (1973). Effects of Photosystem II inhibitors on electron paramagnetic resonance signal II in chioroplasts. Photochem. & Photobiol. 17, 133–7.CrossRefGoogle Scholar
Lozier, R. H. & Butler, W. L. (1974 a). Redox titration of the primary electron acceptor of Photosystem I in spinach chioroplasts. Biochim. biophys. Acta 333, 460–464.CrossRefGoogle Scholar
Lozier, R. H. & Butler, W. L. (1974 b). Light-induced absorbance changes in chioroplasts mediated by Photosystem I and II at low temperature. Biochim. biophys. Acta 333, 465–480.CrossRefGoogle ScholarPubMed
Malkin, R. & Bearden, A. J. (1971). Primary reactions of photosynthesis: Photoreduction of a bound chloroplast ferredoxin at low temperatures as detected by EPR spectroscopy. Proc. natn. Acad. Sci. U.S.A. 68, 16–19.CrossRefGoogle ScholarPubMed
Malkin, R. & Bearden, A. J. (1973). Detection of a free-radical in the primary reaction of chloroplast Photosystem II. Proc. natn. Acad. Sci.U.S.A. 70, 294–7.CrossRefGoogle ScholarPubMed
Malkin, R. & Knaff, D. B. (1973). Effect of oxidizing treatment on chioroplast Photosystem II reactions. Biochim. biophys. Acta 325, 336–40.CrossRefGoogle Scholar
Malkin, S. & Kok, B. (1966). Fluorescence induction studies in isolated chloroplasts. I. Number of components involved in the reaction and quantum yields. Biochim. biophys. Acta 126, 413–32.CrossRefGoogle ScholarPubMed
Malkin, S. & Michaeli, G. (1972). Fluorescence induction studies in isolated chloroplasts. In Proc. 2nd Int. Congr. on Photosynthesis Res. (ed. Forti, G., Avron, M. and Melandri, A.), pp. 149–68. The Hague:Junk.Google Scholar
Mauzerall, D. (1972). Light-induced fluorescence changes in Chiorella, and the primary photoreactions for the production of oxygen. Proc. natn. Acad. Sci. U.S.A. 69, 1358–62.CrossRefGoogle Scholar
Murata, N. (1968). Fluorescence of chlorophyll in photosynthetic systems. IV. Induction of various emissions at low temperatures. Biochim. biophys. Acta 162, 106–21.CrossRefGoogle ScholarPubMed
Murata, N. & Takamiya, A. (1969). Nature of light-induced absorbance changes at 682 mμ and 702 mμ in photosynthesis of Anacystis nidulans. Pl. Cell Physiol. 10, 193–202.Google Scholar
Netzel, T. L., Rentzepis, P. M. & Leigh, J. S. (1973). Picosecond kinetics of reaction centers containing bacteriochiorophyll. Science, N. Y. 182, 238–41.CrossRefGoogle Scholar
Okayama, S. & Butler, W. L. (1972 a). Extraction and reconstitution of Photosystem II. Pl. Physiol. 49, 769–74.CrossRefGoogle ScholarPubMed
Okayama, S. & Butler, W. L. (1972 b). The influence of cytochrome b559 on the fluorescence yield of chioroplasts at low temperature. Biochim. biophys. Acta 267, 523–9.CrossRefGoogle Scholar
Orme-Johnson, W. H. (1973). Iron–sulfur proteins: Structure and function. A. Rev. Biochem. 42, 159–204.CrossRefGoogle ScholarPubMed
Rumberg, B., Schmidt-Mende, P., Weikard, J. & Witt, H. T. (1963). Correlation between absorption changes and electron transport in photosynthesis. In Photosynthetic Mechanisms of Green Plants (ed. Kok, B. and Jagendorf, A. T.), pp. 18–34. Washington, D.C.: National Academy of Sciences–National Research Council.Google Scholar
Ruuge, E. K. & Izawa, S. (1972). The oxidation-reduction potential of P700 in unbroken chloroplasts. Fedn Proc. Fedn Am. Socs exp. Biol. 31, 901, Abs.Google Scholar
Sane, P. V., Goodchild, D. J. & Park, R. B. (1970). Characterization of chioroplast photosystems 1 and 2 separated by a non-detergent method. Biochim. biophys. Acta 216, 162–78.CrossRefGoogle Scholar
Siedow, J., Yocum, C. F. & SanPietro, A. Pietro, A. (1973). The reducing side of Photosystem I. Curr. Top. Bioenerg. 5, 107–23.CrossRefGoogle Scholar
Sogo, P. B., Pon, N. G. & Calvin, M. (1957). Photo spin resonance in chlorophyll-containing plant material. Proc. natn. Acad. Sci. U.S.A. 43, 387–93.CrossRefGoogle ScholarPubMed
Stiehl, H. H. & Witt, H. T. (1968). Die kurzzeitigen ultravioletten Differenzspketren bei der Photosynthese. Z. Naturf. B 23, 220–4.CrossRefGoogle Scholar
Stiehl, H. H. & Witt, H. T. (1969). Quantitative treatment of the function of plastoquinone in photosynthesis. Z. Naturf. B 24, 1588–98.CrossRefGoogle Scholar
Tagawa, K. & Arnon, D. I. (1962). Ferredoxins as electron carriers in photosynthesis and in the biological production and consumption of hydrogen gas. Nature, Lond. 195, 537–43.CrossRefGoogle ScholarPubMed
Thorne, S. W. & Boardman, N. K. (1971). The effect of temperature on the fluorescence kinetics of spinach chloroplasts. Biochim. biophys. Acta 234, 113–25.CrossRefGoogle ScholarPubMed
Vermeglio, A. & Mathis, P. (1973 a). Photooxidation of cytochrome b559 and the electron donors in chloroplast Photosystem II. Biochim. biophys. Acta 292, 763–71.CrossRefGoogle Scholar
Vermeglio, A. & Mathis, P. (1973 b). Photoreduction of C-550 and oxidation of cytochrome b559 in chloroplasts. Dependence on the state of Photo-system II. Biochim. biophys. Acta 314, 57–65.CrossRefGoogle Scholar
Vernon, L. P. & Ke, B. (1966). Photochemistry of chlorophyll in vivo. In The Chlorophylls (ed. Vernon, L. P. and Seely, G. R.), pp. 569–608. New York: Academic Press.CrossRefGoogle Scholar
Vernon, L. P., Ke, B. & Shaw, E. (1967). Relationship of P700, electron spin resonance signal and photochemical activity of a small chloroplast particle obtained by the action of Triton X-100. Biochemistry, N. Y. 6, 2210–20.CrossRefGoogle ScholarPubMed
Vernon, L. P. & Shaw, E. R. (1971). Subchloroplast fragments: Triton X-100 method. Meth. Enym. 23, 277–89.Google Scholar
Wang, J. H. (1970). Oxidative and photosynthetic phosphorylation mechanisms. Science, N.Y. 167, 25–30.CrossRefGoogle ScholarPubMed
Warden, J. T. Jr & Bolton, J. R. (1972). Simultaneous optical and electron spin resonance detection of the primary photoproduct P700 in green plant photosynthesis. J. Am. chem. Soc. 94, 4352–3.CrossRefGoogle Scholar
Warden, J. T. Jr & Bolton, J. R. (1973). Simultaneous quantitative comparison of the optical changes at 700 nm (P700) and electron spin resonance signals in System I of green plant photosynthesis. J. Am. them. Soc. 95, 6435–6.CrossRefGoogle Scholar
Weaver, E. C. (1968). EPR studies of free radicals in photosynthetic systems. A. Rev. Pl. Physiol. 19, 283–94.CrossRefGoogle Scholar
Weaver, E. C. & Bishop, N. I. (1963). Photosynthetic mutants separate electron paramagnetic resonance signals of Scenedesmus. Science, N. Y. 140, 1095–7.CrossRefGoogle ScholarPubMed
Weaver, E. C. & Weaver, H. E. (1969). Paramagnetic unit in spinach subchloroplast particles: Estimation of size. Science, N.Y. 165, 906–7.CrossRefGoogle ScholarPubMed
Weaver, E. C. & Weaver, H. E. (1972). Electron resonance studies of photosynthetic systems. In Photophysiology (ed. Giese, A. C.) 7, 1–32. New York: Academic Press.Google Scholar
Wessels, J. S. C., Van, Alphen-vanwaveren, O. & Voorn, G. (1973). Isolation and properties of particles containing the reactioncenter complex of Photosystem II from spinach chloroplasts. Biochim. biophys. Acta 292, 741–52.CrossRefGoogle Scholar
Witt, K. & Wolff, Ch. (1970). Rise time of the absorption changes of chlorophyll-a1 and carotenoids in photosynthesis. Z. Naturf. B 25, 387–8.CrossRefGoogle Scholar
Yamamato, H. Y. & Vernon, L. P. (1969). Characterization of a partially purified photosynthetic reaction center from spinach chloroplasts. Biochemistry, N.Y. 8, 4131–7.CrossRefGoogle Scholar
Yang, C. S. & Blumberg, W. E. (1972). Quantitative studies on the EPR signals of photosynthetic System I and ferredoxin. Biochem. biophys. Res. Commun. 46, 422–8.CrossRefGoogle Scholar
Yocum, C. F. & San, Pietro A. (1969). Ferredoxin reducing substance (FRS) from spinach. Biochem. biophys. Res. Commun. 36, 614–20.CrossRefGoogle ScholarPubMed
Yocum, C. F. (1971). Ph.D. Dissertation, Indiana University.Google Scholar
Zweig, G. & Avron, M. (1965). On the oxidation-reduction potential of the photoproduced reductant of isolated chloroplasts. Biochem. biophys. Res. Commun. 19, 397–400.CrossRefGoogle ScholarPubMed
Zweig, G., Shavit, N. & Avron, M. (1965). Diquat in photoreactions of isolated chloroplasts. Biochim. biophys. Acta 109, 332–46.CrossRefGoogle ScholarPubMed