Selected Scientists

ARNOLD is the co-discoverer of the concept of "photosynthetic unit" (with Emerson); delayed light emission (with B. Strehler); thermoluminescence ( with H. Sherwood); and electroluminescence ( with J. Azzi) in photosynthetic tissues; and the concept that primary photochemistry in these tissues occurs down to 1 K (with R. Clayton).
SEE: W.A. Arnold (1991) Experiments. Photosynth. Res. 27: 73-82. ALSO, WATCH FOR THE SPECIAL ISSUE OF "Photosynthesis Research": "Photosynthetic Unit: Antenna and Reaction Center" to be available around September/October, 1996.

DUYSENS is known, among other discoveries, for demonstrating excitation energy transfer from antenna pigments to reaction centers in many photosynthetic systems; for showing absorption changes in the reaction center bacteriochlorophyll molecules; for the "push-pull" effect on the redox state of cytochrome f by photosystems II and I, respectively , and, thus establishing the "Z"- scheme of photosynthesis (with J. Amesz); for the concept that the oxidized form of the "primary" electron acceptor of photosystem II, Qa, is a quencher of chlorophyll a fluorescence.
SEE: L.N.M. Duysens (1989) The discovery of the two photosynthetic systems: a personal account. Photosynth Res. 21: 61-79.

EMERSON is known, among many discoveries, for establishing the concept of "photosynthetic unit" in photosynthesis (with Arnold); for establishing that the minimum quantum yield of oxygen evolution is 8-10 quanta per oxygen evolved (with C.M. Lewis and others); and for the existence of two-light reaction and two-photosystem concept of photosynthesis through his discoveries of the "Red Drop" (with Lewis) and the ( Emerson) Enhancement effect in photosynthesis.
SEE: E. Rabinowitch (1959) Robert Emerson 1903-1959. Plant Physiol. 34: 179-184; Biographical Memoirs of the National Academy of Sciences of the United States, 35: 112-131.

FRENCH is known, among many discoveries, for establishing and naming the "chloroplast reaction", the "Hill reaction"; for the existence of excitation energy transfer from phycoerythrin to chlorophyll a ; for the existence of several spectral forms of chlorophyll a in vivo; and for the innovation of the so-called "French press", among many other instruments.
SEE: C.S. French (1979) Fifty years of photosynthesis. Ann. Rev. Plant Physiol. 30 : 1 -26. ALSO, WATCH for a Tribute writtten by D.C. Fork, to appear in Photosynth. Res. in 1996.

RABINOWITCH is known as the "prophet" and the writer of the "Bible of Photosynthesis "; for the first use of a "difference absorption spectrophotometer" in any field; for the proposal of a scheme of photosynthesis that looks very much like the current "Z" scheme of photosynthesis (1945); for predicting the reaction center of photosystem II "P-680" (1965) before its discovery; for proposing that one light reaction oxidizes cytochrome f and the other reduces it predicting the experimental evidence for the "Z" scheme already in 1956; for the first correct measurements on the quantum yield of fluorescence in vivo (with P. Latimer); and for the first measurements on the lifetime of fluorescence ( with S. Brody), and for establishing (with Govindjee) that both light reactions of photosynthesis are sensitized by chlorophyll a, but of different spectral form, and for the demonstration of the two-light effect (with Govindjee) through antagonistic effect of different wavelengths of light on chlorophyll a fluorescence.
SEE: E. Rabinowitch (1945) Photosynthesis, volume I, p. 162 (Scheme 7.V); and (1956) Photosynthesis, volume II, part II, p. 1862, Interscience Publishers, N.Y.; E. Rabinowitch and Govindjee ( 1965) The role of chlorophyll in photosynthesis. Scientific American 213: 74-83; T.T. Bannister (1972) The careers and contributions of Eugene Rabinowitch. Biophys. J. 12: 707-718; S.S. Brody (1995) We remember Eugene. Photosynth. Res. 43: 67-74.

OTTO WARBURG 1931 Nobel laureate in Physiology and Medicine, from Berlin Germany. Died in 1970.

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Last page update: 18 September 1999