Inhibition of Photosynthetic Electron Transport by the Quinone Antagonist UHDBT
نویسندگان
چکیده
Quinone, Photosynthetic Electron Transport, Inhibitor UHDBT (5-«-undecyl-6-hydroxy-4,7-dioxobenzothiazole) is an efficient inhibitor of photosyn thetic electron transport in chloroplasts from spinach (pl50-value = 7.61) and the green alga Chlamydomonas reinhardii. At low concentrations of UHDBT its site of inhibition is located at the reducing side of plastoquinone, identical to that of 3-(3,4-dichlorophenyl)-l,l-dimethylurea (DCMU). This became evident from functional as well as binding studies. At higher concentra tions of UHDBT a secondary inhibition site at the oxidizing side of plastoquinone, identical to that of 2,5-dibromo-3-methyl-6-isopropyl-l,4-benzoquinone (DBMIB) becomes evident.
منابع مشابه
The Nature of the Inhibition of 4,7-Dioxobenzothiazole Derivatives on Mitochondrial Ubiquinol-Cytochrome
To investigate the inhibitory action and binding site of a quinone-like molecule, S-undecyl-6-hydroxy-4,7dloxobenzothiazole (UHDBT), a series of 4,?-dioxobenzothiazole derivatives were synthesized and their inhibitory efficiencies studied. Replacing the 6-hydroxyl or 2-hydrogen of UHDBT with a bromo or a methoxy group causes only a slight decrease in inhibitory efficiency, indicating that the 6...
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