Nickel(II) salts and their coordination compounds with ethyl 5-methylimidazole-4-carboxylate (emizco), [Ni(emizco)2Cl2], [Ni(emizco)2Br2], [Ni(emizco)2(H2O)2](NO3)2·H2O, Ni(NO3)2, inhibit photosynthetic electron flow (basal, phosphorylating and uncoupled) and ATP-synthesis, therefore behave as Hill reaction inhibitors. Coordination compounds are more potent inhibitors than the salts. It was found that the target for NiCl2; NiBr2 and Ni(NO3)2 is at the b6f level. On the other hand, the complexes [Ni(Emizco)2Cl2], [Ni(Emizco)2Br2] and [Ni(emizco)2(H2O)2](NO3)2·H2O binding sites are located at Q(B)(D1)-protein and b6f level. Therefore, they have a common inhibition site located at b6f avoiding the PQH2 oxidation. The Q(B) inhibition site was corroborated by variable chlorophyll a fluorescence yield [V(j)]. The emizco ligand has no activity on photosynthetic electron flow.
|Original language||English (US)|
|Number of pages||8|
|Journal||Zeitschrift fur Naturforschung - Section C Journal of Biosciences|
|State||Published - 1998|
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)