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

Inhibition of Photosynthetic Electron Transport by Some Anilides of 2-Alkylpyridine-4-carboxylic Acids in Spinach Chloroplasts

K. Kráľová, F. Šeršeň, M. Miletín, and J. Hartl

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

Abstract: The inhibitory activity of some anilides of 2-alkylpyridine-4-carboxylic acids on oxygen evolution rate in spinach chloroplasts as well as the mechanism and site of action of these compounds in the photosynthetic apparatus of chloroplasts have been investigated. Using ESR spectroscopy it was confirmed that the site of action of the studied anilides are the intermediates Z⁺/D⁺, i.e. tyrosine radicals, which are situated in D₁ and D₂ proteins on the donor side of photosystem 2. The biological activity of the tested compounds was affected by lipophilicity of the substituents on the phenyl ring of the anilide part of the molecule (halogen, methyl, hydroxy) and of the 2-alkyl substituent as well.

Full paper in Portable Document Format: 521a52.pdf

Chemical Papers 52 (1) 52–55 (1998)