Photosynthetica 2002, 40(1):31-34 | DOI: 10.1023/A:1020177703457

Elucidation of the Primary Events in Photosynthesis. Novel Insights Based on Enolisation and Iminium Involvement with Pheophytin in Photosystem 2

P. Kovacic1
1 Discipline of Chemistry, School of Biological and Chemical Sciences, The University of Newcastle, Callaghan, Australia

Pheophytin (Pheo) is structurally constituted as to make possible certain reactions, previously given very little attention, which appear to play crucial roles in the initial electron transfer (ET) processes. The transformations involve enolisation with subsequent formation of mono- and di-iminium cations at the Pheo core. The important impact of these ions on ET from chlorophyll (Chl) to Pheo and then to quinone are evaluated. These insights rationalise the long-standing enigmas of fast transfer, across gap ET, activation-less aspect, and essential lack of reversibility. Comparisons are made to other important areas of iminium involvement, e.g. chemistry of vision, polyaniline doping, and DNA alkylation.

Additional key words: chlorophyll; electron transfer; electrostatics; enigma elucidation

Published: March 1, 2002  Show citation

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Kovacic, P. (2002). Elucidation of the Primary Events in Photosynthesis. Novel Insights Based on Enolisation and Iminium Involvement with Pheophytin in Photosystem 2. Photosynthetica, 40(1), 31-34. doi: 10.1023/A:1020177703457
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