ATP synthesis and pyrophosphate-driven proton transport in tonoplast-enriched vesicles isolated from Catharanthus roseus
نویسندگان
چکیده
In the presence of PP, as an energy source, the tonoplast-bound inorganic pyrophosphatase from Catharanthus roseus cells is able to create a proton-gradient which can drive the synthesis of ATP from ADP and Pi. ATP synthesis is linked to the pH-gradient dissipation as monitored by the recovery of the fluorescence intensity of quinacrine and by the amount of synthesized ATP measured by the bioluminescent luciferin/luciferase assay. Proton gradient and ATP synthesis were suppressed by the protonic ionophore gramicidin D.
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