Over-excitation of photosynthetic apparatus causing photoinhibition is counteracted by non-photochemical quenching (NPQ) of chlorophyll fluorescence, dissipating excess absorbed energy into heat. The PsbS protein plays a key role in this process, thus making the PsbS-less npq4 mutant unable to carry out qE, the major and most rapid component of NPQ. It was proposed that npq4 does perform qE-typ...

We designed and developed a novel heavy metal ion sensing device, based on quenching mechanism, exploiting the characteristics of a polyelectrolyte nanostructured system, named nanocapsule[1]. Nanocapsule allows to entrap fluorescent probes sensitive to a specific metal ion, localizing fluorescent signal in a nano-bordered site within the outermost layers and improving the signal to noise ratio...

Violaxanthin de-epoxidation, chlorophyll fluorescence quenching, and photosynthetic O(2) evolution in the presence of paraquat (Pq) were studied in intact attached leaves of Pq-susceptible, and Pq-resistant (PqR) biotypes of Erigeron canadensis under different light conditions. Initially, similar changes were induced in the two biotypes, but the effects relaxed only in the PqR plants, indicatin...