Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

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

08.11.2013
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.

In 2004, Johnson was a member of the team that determined the molecular structure of a circadian clock protein for the first time. Subsequent work mapped the entire clock mechanism in cyanobacteria, which is the simplest bioclock found in nature. The researchers discovered that the clock consisted of three proteins: KaiA, KaiB and KaiC. Detailed knowledge of the clock’s structure allowed them to determine how to switch the clock on and off.

In the current study, the researchers discovered that two components of the clock, KaiA and KaiC, act as switches that turn the cell’s daytime and nighttime genes on and off. They have dubbed this “yin-yang” regulation.

When KaiA is upregulated – produced in larger amounts – and KaiC is downregulated – produced in smaller amounts – then the 95 percent of cell’s genes that are active during daylight are turned on, and the 5 percent of the cell’s genes that operate during the night are turned off. However, when KaiC is upregulated and KaiA is downregulated then the day genes are turned off and the night genes are turned on.

“As a result, all we have to do to lock the biological clock into its daylight configuration is to genetically upregulate the expression of KaiA, which is a simple manipulation in the genetically malleable cyanobacteria,” Johnson said.

To see what effects this capability has on the bacteria’s ability to produce commercially important compounds, the researchers inserted a gene for human insulin in some of the cyanobacteria cells, a gene for a fluorescent protein (luciferase) in other cells and a gene for hydrogenase, an enzyme that produces hydrogen gas, in yet others. They found that the cells with the locked clocks produced 200 percent more hydrogenase, 500 percent more insulin and 700 percent more luciferase when grown in constant light than they did when the genes were inserted in cells with normally functioning clocks.

Coauthors of the study include Research Associate Professor Yao Xu, Postdoctoral Fellow Ximing Qin and Graduate Student Jing Xiong from Vanderbilt; Assistant Professor Philip Weyman and Group Leader Qing Xu from the J. Craig Venter Institute in Rockville, Md., and Graduate Student Miki Umetani and Professor Hideo Iwasaki at Waseda University in Tokyo.

The research was funded by National Institute of General Medical Sciences grants GM067152 and GM088595, Department of Energy grant DE-FG36-05GO15027, Japanese Society for the Promotion of Science grants 23657138 and 23687002, the Asahi Glass Foundation and the Yoshida Scholarship Foundation.

Visit Research News @ Vanderbilt for more research news from Vanderbilt. [Media Note: Vanderbilt has a 24/7 TV and radio studio with a dedicated fiber optic line and ISDN line. Use of the TV studio with Vanderbilt experts is free, except for reserving fiber time.]

David F. Salisbury | Vanderbilt University
Further information:
http://www.vanderbilt.edu

More articles from Life Sciences:

nachricht Show me your leaves - Health check for urban trees
12.12.2017 | Gesellschaft für Ökologie e.V.

nachricht Liver Cancer: Lipid Synthesis Promotes Tumor Formation
12.12.2017 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Long-lived storage of a photonic qubit for worldwide teleportation

12.12.2017 | Physics and Astronomy

Multi-year submarine-canyon study challenges textbook theories about turbidity currents

12.12.2017 | Earth Sciences

Electromagnetic water cloak eliminates drag and wake

12.12.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>