Crop Biotech Update

Scientists Identify Proton Pathway in Photosynthesis

April 24, 2013

Photosynthetic organisms like plants convert sunlight, carbon dioxide, and water into chemical energy stored in the membrane of special cells through a process similar to charging a battery. To further understand this mechanism of "charging", scientists at Purdue University investigated a proton transfer pathway involved in energy storage in photosynthesis.

William Cramer and colleagues used X-ray crystallography to study the pathway of the cytochrome complex, which is a group of proteins that transport most of the protons that energize the plant cell "battery". These proteins are composed of various amino acid sequences, including those that are involved in the "bucket brigade" of proton transfer. The scientists provided a structure-based description of the quinone-mediated proton transfer responsible for generation of the transmembrane electrochemical potential gradient in oxygenic photosynthesis.

The research paper is published in the Proceedings of National Academy of Sciences is available at: