The Present Status of the Comparative Study of Photosynthesis

Niel, Cécile

doi:10.1146/annurev.pp.13.060162.000245

Cited by 26 publications

(5 citation statements)

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“…Soon I was given the opportunity to present a seminar based on van Niel's paper. This was the beginning of a lasting friendship with 'Kees', as his friends called him, the great authority on microbiology, photosyntheses and a deeper understanding of life processes (van Niel 1941(van Niel , 1962. Curiously, I made an impression on Professor van Niel by providing him with information I had obtained from the study of the 'Outlines of Bio-chemistry' by Ross Aiken Gortner (1938).…”

Section: University Of California At Berkeley: Sam Ruben and Martin Kmentioning

confidence: 99%

Recollections

Frenkel

1993

Photosynth Res

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About 1939, Sam Ruben and Martin Kamen introduced me to the emergent application of artificial radio-isotopes in the study of photosynthesis. While my own experiments on CO2 fixation by isolated chloroplasts turned out to be negative, their laboratory provided me with an informative and exciting experience. Also, there were many stimulating contacts with Cornelis van Niel, Robert Emerson, Don DeVault and many other outstanding scientists. Efforts on my part to obtain a better understanding of intermediary metabolism, eventually led me to Fritz Lipmann's laboratory. There I was encouraged to study the metabolic activities of cell-free preparations of photosynthetic purple bacteria. Investigations of oxidative phosphorylation by isolated bacterial chromatophores in the dark raised questions about the possible effects of light on the phosphorylation activities of such preparations. Surprisingly, high rates of phosphorylation were observed in the light in the absence of molecular oxygen ('light-induced phosphorylation'). In this process, adenosine diphosphate (ADP) and inorganic phosphate (Pi) could be converted quantitatively into adenosine triphosphate (ATP). It was postulated that this process was 'cyclic' in nature, as only catalytic concentrations of added electron donors were required. Later, at Minnesota, it could be shown that similar chromatophore preparations, in the presence of suitable electron donors, could reduce nicotinamide-adenine dinucleotide (NAD(+)) to NADH in the light. It was then demonstrated that the chromatophores of Rhodospirilum rubrum, as well as the smaller membrane components derived from them, must contain the active metabolic components for these photosynthetic reactions.These observations, and studies on the kinetics of the formation and decay of light-induced free radicals, appeared to demonstrate the usefulness of bacterial chromatophores and of their membrane fragments in the study of partial reactions of bacterial photosynthesis. Since that time, numerous investigators elsewhere have carried out remarkable research on the purification and eventual crystallization of distinct bacterial membrane components, capable of carrying out well characterized photochemical and electron transport reactions.

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Section: University Of California At Berkeley: Sam Ruben and Martin Kmentioning

confidence: 99%

Recollections

Frenkel

1993

Photosynth Res

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“…Several authors 5 ' 7-10 presented the theory that the photooxidation of water could be brought about by the oxidation of OH G -ions to OH radicals or equivalents of these [11][12][13][14][15] the recombination of which w r ould lead to H20 and 02 .…”

Section: Oh-radical Model For Photosynthetic Water Oxidationmentioning

confidence: 99%

On the Impossibility of an OH-Radical Model for Photosynthetic Water Oxidation / Über die Unmöglichkeit eines OH-Radikalmodells für die photosynthetische Wasseroxidation

Vierke

1972

Zeitschrift Für Naturforschung B

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OH-Radical Model for Photosynthetic Water OxidationIf it is assumed that the oscillating 02 flash yield sequence of algae and chloroplasts predominantly reflects an inherent property of the 02 evolving system of the photosynthetic apparatus it is shown that the OH-radical model (02 production by recombination of four OH radicals) is contradictory to the experimental results because it predicts an aperiodic 02 flash yield sequence.Several experimental facts already known strongly indicate that the OH-radical model is not consistent with the kinetic model for 02 evolution of KOK et al. either. In spite of extensive research in photosynthesis our knowledge of the structure and activities of photosystem II because of its complexity is rather limited. Although considerable progress has been made in recent years the specific mechanism for the photosynthetic oxidation of water to molecular oxygen remains to be elucidated. Several models for this process have been proposed based on a molecular or solid state theory of the primary events of photosynthesis. The kinetic models of KOK et al. *' 2 and of JOLIOT et al. 3 were developed in order to explain the 02 flash yield sequence observed on algae and chloroplasts by these authors. The first model on a specific molecular basis was presented by RENGER 4 . He demonstrated that the 02 flash yield pattern could be deduced quantitatively from several assumptions on the molecular structure of the 02 evolving enzyme system. Although it is not known whether there are "free" oxygen intermediates in photosynthetic water oxidation it is assumed in this model as well as in that of JOLIOT et al. that the water cleavage leads to the production of oxygen atoms which combine to form 02 .According to the solid state theory of photosynthetic 02 evolution the decomposition of the water molecule is thought to be caused by its interaction with randomly diffusing molecular excitons of the chlorophyll aggregates at the surface of the thylakoid membrane 5 ' 6 . But no explanation for the 02Requests for reprints should be sent to Dr. G. VIERKE, Institut für physikalische Biochemie der Universität Frankfurt, D-6000 Frankfurt, Sandhofstr. 2. flash yield pattern in terms of the solid state theory has been offered as yet.Several authors 5 ' 7-10 presented the theory that the photooxidation of water could be brought about by the oxidation of OH G -ions to OH radicals or equivalents of these 11-15 the recombination of which w r ould lead to H20 and 02 .In this paper it is shown that the OH-radical model of photosynthetic water oxidation cannot provide an explanation for the 02 flash yield oscillations as determined by JOLIOT et al. 3 and KOK et al. 2 . Some Operational and Structural Principles of PS IIOnly the most important facts concerning the 02 evolution mechanism will be reported in the following short summary. Details which are not necessary for the subsequent proof have been omitted.Since 02 evolution is a four quantum process 16 ' 17 (quantum requirement of PS II) the oxidation of water to m...

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“…I n bacterial photosynthesis an external reductant is required for the fixation of carbon dioxide or for photo-heterotrophic growth (van Niel, 1935(van Niel, , 1941(van Niel, , 1962Stanier, 1961 ;Gest, 1966). I n a similar manner an added reductant (AH,) is required for the light-induced reduction of nicotinamide-adenine dinucleotide (NAD) by isolated chromatophores (Frenkel, 1958(Frenkel, , 1959a (4) Present experimental evidence points to two mechanism by which NAD (or in certain cases NADP) reduction can be accomplished.…”

Section: ( 3 ) Light-induced Reduction Of Nicotinamide-adenine Dinuclmentioning

confidence: 99%

“…T h e recent literature on photosynthetic bacteria and their photosynthetic activities have been extensively summarized and analysed in a number of recent reviews (van Niel, 1962(van Niel, , 1967Vernon, 1964Vernon, , 1968Duysens & Amesz, 1967;Pfennig, 1967;Lascelles, 1968u, b ;Doelle, 1969), in several books devoted entirely to this subject (Gest, San Pietro & Vernon, 1963;Kondrat'eva, 1965) and in portions of books, symposia, and reviews devoted in part to certain aspects of bacterial photosynthesis (Kamen, 1 9 6 3~; Clayton, 1965;Hill, 1965;Vernon & Seely, 1966;Gest, 1966;Olson, Hind, Lyman & Siegelman, 1967;Arnon, 1967;Gibbs, 1967;Bendall & Hill, 1968;Hind & Olson, 1968;Weaver, 1968;Rabinowitch, 1945Rabinowitch, , 1951Rabinowitch, , 1956Rabinowitch & Govindjee, 1969;Fork & Amesz, 1969).…”

Section: Introductionmentioning

confidence: 99%

Multiplicity of Electron Transport Reactions in Bacterial Photosynthesis

Frenkel¹

1970

Biological Reviews

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The Present Status of the Comparative Study of Photosynthesis

Cited by 26 publications

References 50 publications

Recollections

Recollections

On the Impossibility of an OH-Radical Model for Photosynthetic Water Oxidation / Über die Unmöglichkeit eines OH-Radikalmodells für die photosynthetische Wasseroxidation

Multiplicity of Electron Transport Reactions in Bacterial Photosynthesis

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