ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Effect of Chromone-Substituted Benzothiazolium Halides on Photosynthetic Processes

K. Kráľová, F. Šeršeň, R. Gašparová, and M. Lácová

Institute of Chemistry, Faculty of Natural Sciences, Comenius University, SK-842 15 Bratislava

Abstract: The effects of 3-R²-2-[2-(6-R¹-chromon-3-yl)ethenyl]benzothiazolium halides (CBH) on photosynthetic electron transport in spinach chloroplasts and in the algal suspension of Chlorella vulgaris were investigated. Using EPR spectroscopy it was confirmed that these compounds containing in their molecules two heterocyclic skeletons, namely bienzothiazole and chromone, interact with the intermediate D⁺, corresponding to the tyrosine radical Tyr_D situated in D₂ protein on the donor side of photosystem 2. Consequently, higher concentrations of CBH inhibited oxygen evolution rate in Chlorella, vulgaris and the inhibitory effectiveness depended on the lipophilicity of the compound.

Full paper in Portable Document Format: 526a776.pdf

Chemical Papers 52 (6) 776–779 (1998)