Study Solves Longstanding Mystery of Photosynthesis

Researchers from Louisiana State University (LSU), the Palacký University in the Czech Republic and at the University of Cincinnati in Ohio have solved a longstanding mystery in photosynthesis.

The protein complex Photosystem II, a vital player in photosynthesis, paralyzes itself by producing harmful reactive oxygen species, such as water molecules with too few electrons and oxygen molecules with too many. While Photosystem II produces oxygen, it also damages itself in the process, which results in up to 20 percent reduction in its productivity during daylight hours. Scientists still do not understand exactly how this happens, or exactly how and where the damage to Photosystem II occurs.

The research team found that a hydroxyl radical and a superoxide, types of reactive oxygen species, are damaging Photosystem II during photosynthesis. They have also identified the specific regions of the Photosystem II protein complex where these reactive oxygen species wreak havoc. The researchers found that regions of Photosystem II closest to where the reactive oxygen species are created during photosynthesis are damaged first, in regions of two proteins they identified as D1 and D2, and located the areas in Photosystem II that are most susceptible to damage.

For more details about this research, read the article at the LSU Media Center.