January 5, 2013

Photosynthesis - The last link in the chain




For almost 30 years, researchers have sought to identify a particular enzyme that is involved in regulating electron transport during photosynthesis. An LMU team has now found the missing link, which turns out to be an old acquaintance.

Photosynthesis sustains life on Earth by providing energy-rich compounds and the molecular oxygen that higher organisms depend on. The process is powered by sunlight, which is captured by “biochemical solar cells” called photosystems that are found in plants, algae and certain types of bacteria. Plants have two photosystems, PSI and PSII. Each consists of a pigment-protein complex that uses solar energy to raise electrons to a higher energy level. These are then passed along a chain of electron acceptors, and the energy released is employed for synthesis of ATP, the “coinage” used for all energy transactions in cells.