A blue stoplight to prevent runaway photosynthesis

A blue stoplight to prevent runaway photosynthesis
Okazaki Large Spectrograph in Japan, where the action spectra of qE quenching were recorded. Credit: NIBB

Through photosynthesis, solar energy is converted into biological energy. It is often thought that photosynthesis becomes stronger as light becomes stronger, but actually photosynthesis may run out of control if subjected to an overabundance of light, causing reactive oxygen species which break the photosynthetic apparatus. To avoid this, when exposed to intense light plants have a mechanism called "qE quenching" to prevent runaway photosynthesis by converting the excess energy to heat and discarding it.

An international team including researchers in France and Japan, using the green alga Chlamydomonas as a model, found a switch that triggers the suppression mechanism to prevent runaway . The switch is a photoreceptor protein called phototropin. The research has been published in the September 22 issue of Nature.

Professor Jun Minagawa of the National Institute for Basic Biology in Japan said "Too much direct sunlight is a painful thing for humans, and it is painful even for plants. Being in an environment where direct sunlight pours down all year round is a big burden for plants. We now know that within plants information regarding the active state of photosynthesis, combined with the sensing of blue light, fit together to activate the photosynthesis suppressing 'qE quenching' system." Drs. Dimitris Petroutsos and Giovanni Finazzi of the French National Center for Scientific Research (CNRS) have said "We looked at what have so far been considered to be completely separate phenomena, the perception of blue light by phototropin, photosynthesis by chlorophyll, and light protection by qE quenching, and to find that these three systems are connected at the molecular level has made us very happy."

This blue stoplight photosynthesis inhibiting system is believed to be shared among algae, moss, and other plants. It is expected to be useful in the optimization of applications such as biofuel production.


Explore further

Newly discovered algal enzyme could help improve efficiency of photosynthesis and boost crop productivity

More information: Dimitris Petroutsos et al. A blue-light photoreceptor mediates the feedback regulation of photosynthesis, Nature (2016). DOI: 10.1038/nature19358
Journal information: Nature

Provided by National Institute for Basic Biology
Citation: A blue stoplight to prevent runaway photosynthesis (2016, September 27) retrieved 19 September 2019 from https://phys.org/news/2016-09-blue-stoplight-runaway-photosynthesis.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
9 shares

Feedback to editors

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more