Photoinhibition — a historical perspective (original) (raw)

2005, Advances in Photosynthesis and Respiration

Photoinhibition is a state of physiological stress that occurs in all oxygen evolving photosynthetic organisms exposed to light. The primary damage occurs within the reaction center of Photosystem II (PS II). While irreversible photoinduced damage to PS II occurs at all light intensities, the efficiency of photosynthetic electron transfer decreases markedly only when the rate of damage exceeds the rate of its repair, which requires de novo PS II protein synthesis. Photoinhibition has been studied for over a century using a large variety of biochemical, biophysical and genetic methodologies. The discovery of the light induced turnover of a protein, encoded by the plastid psbA gene (the D1 protein), later identified as one of the photochemical reaction center II proteins, has led to the elucidation of the underlying mechanism of photoinhibition and to a deeper understanding of the PS II 'life cycle.' Abbreviations: bRC -bacterial reaction center; Chl -chlorophyll; DCIP -dichlorophenol-indophenol; DCMU -3-(3,4, dichlorophenyl) 1,1-dimethylurea; EMBO -European Molecular Biology Organization; kDa -kilo Dalton, apparent; LMW -low molecular weight proteins of PS II; NASA -National Aeronautics Space Agency; pD1 precursor -carboxy-terminal unprocessed D1 protein; Pheo -the primary PS II electron acceptor; Pheo .−.pheophytin anion radical; PI -photoinhibition; PS I, PS II -photosystem I and II respectively; Q A -Q B -Q A .− -Q B .− -the primary and secondary electron acceptors quinones of PS II in the oxidized and semiquinone radical form, respectively; RCII -photosystem II reaction center; S 2 -S 3 -the oxidation states of the manganese cluster of PS II donor side that has lost one or two electrons, respectively; Y Z , Y Z .− -the tyrosine 161 of the D1 protein in the neutral and anion radical form, respectively Participants at the EMBO (European Molecular Biology Organization) Workshop on Photosystem II Dynamics held in Jerusalem, Israel, 1987. First row (left to right): Aviah Zilberstein, Franklin Callahan, Anastasios Melis, the late Philip Thornber, Itzhak Ohad and Marvin Edelman (organizers); Shmuel Malkin and Mordechai Avron are the last two in this row. Second row, (left to right): (last). Third row (left to right): Aaron Kaplan (2nd), Joseph Hirschberg (3rd), Bruce M. Greenberg (6th, behind and on the left of N. Murata), Paul Mathis (7th, behind O Canaani), Gunnar Oquist (wearing glasses), Jonathan Gressel (behind N. Adir); John Bennett is behind and between S. Golden and E. Tobin; Achim Trebst and Gernot Renger (last two). Last row (left to right): Victor Gaba (behind and to the left of B. Greenberg), Wim Vermaas (beard and glasses), Hartmut Michel (behind C. Critchley), Judith St. John (right to J. Gressel), John Gray (behind S. Golden), Bertil Andersson and Jim Barber (last). Photo provided by Itzhak Ohad.