Method gets the measure of photocurrents from proteins

The team, led by Joachim Reichert, Johannes Barth, and Alexander Holleitner (Technische Universitaet Muenchen, Clusters of Excellence MAP and NIM), and Itai Carmeli (Tel Aviv University) demonstrated that such a system can be integrated and selectively addressed in artificial photovoltaic device architectures while retaining their biomolecular functional properties.

The proteins are said to represent light-driven, highly efficient single-molecule electron pumps that can act as current generators in nanoscale electric circuits.

According to a statement, the scientists investigated the photosystem-I reaction centre, which is a chlorophyll protein complex located in membranes of chloroplasts from cyanobacteria.

Plants, algae and bacteria use photosynthesis to convert solar energy into chemical energy.

The initial stages of this process — where light is absorbed and energy and electrons are transferred — are mediated by photosynthetic proteins composed of chlorophyll and carotenoid complexes.

Until now, none of the available methods were sensitive enough to measure photocurrents generated by a single protein.