Tricking algae's biological clock boosts production of drugs, biofuels

Tricking algae's biological clock to remain in its daytime setting can dramatically boost the amount of valuable compounds that these simple marine plants can produce when they are grown in constant light.

That is the conclusion of a "proof of concept" experiment described in the Dec. 2 issue of the journal Current Biology. The study found that when the biological clocks of cyanobacteria (blue-green algae) were stopped in their daylight setting, the amount of several biomolecules that they were genetically altered to produce increased by as much as 700 percent when grown in constant light.

"We have shown that manipulating cyanobacteria's clock genes can increase its production of commercially valuable biomolecules," said Carl Johnson, Stevenson Professor of Biological Sciences at Vanderbilt University, who performed the study with collaborators at the J. Craig Venter Institute in Rockville, MD and Waseda University in Tokyo. "In the last 10 years, we have figured out how to stop the circadian clocks in most species of algae and in many higher plants as well, so the technique should have widespread applicability."

If it lives up to its promise, bioclock stopping could have significant economic benefits: Microalgae are used for a wide variety of commercial applications ranging from anti-cancer drugs to cosmetics to bioplastics to biofuels to neutraceuticals. In addition, biotech companies are currently rushing to set up "biofactories" that use microorganisms to create a wide variety of substances that are too difficult or expensive to synthesize using conventional chemical methods. Many of them are based on microorganisms that have biological clocks.