Researchers decipher the molecular basis of blue-green algae

Aug 01, 2011

Under normal conditions, cyanobacteria, also termed blue-green algae, build up energy reserves that allow them to survive under stress such as long periods of darkness. They do this by means of a molecular switch in an enzyme. By removing this switch, it should be possible to use the excess energy of the bacteria for biotechnological purposes such as hydrogen production, without the bacteria suffering.

This was found out by researchers at the Ruhr-Universität led by Prof. Dr. Matthias Rögner (Biochemistry of Plants, Faculty of Biology and Biotechnology). Their results, which they obtained together with a Japanese research group from the Tokyo Institute of Technology, are published in the Journal of Biological Chemistry.

Molecular switch prevents waste of energy

The energy-rich molecule ATP serves as a store for the energy gained through photosynthesis in plants. It is built up, and where necessary broken down again, by the enzyme ATPase. To guard the bacterium against stress situations with too much or too little light, the ATPase of the cyanobacteria has a small area which acts like a switch. It prevents the ATP from being broken down prematurely in the dark, when no photosynthesis takes place. The bacterium thus creates a store of energy which helps it through stress phases. However, this switch also slows the rate of photosynthetic electron transport with the water splitting in light: "You have to imagine it like wanting to squeeze something into a full storehouse against resistance", says Prof. Rögner.

On the way to biotechnological hydrogen

In the experiment, he and his colleagues removed the switch area of the ATPase in cyanobacteria by means of genetic engineering. "Of course we expected that the bacteria would suffer much more afterwards and that they would become much slower", he explains. "But that was not the case". The grew just as usual under laboratory conditions - without light stress. However, they create lower ATP energy reserves, so they can't survive very long dark periods as well as the wild type. On the other hand, the in light, which otherwise went into the reserves, is now available for biotechnological use. "This should make it possible to use at least 50% of the energy gained from light-driven water splitting for other processes in the future, e.g. for solar-powered biological through cyanobacterial mass cultures in photobioreactors", estimates Prof. Roegner.

Explore further: Researcher among best in protein modeling contests

More information: J. Biol. Chem. 286, 26595-26602, doi: 10.1074/jbc.M111.234138

Related Stories

Oxygen levels in the air do not limit plant productivity

Feb 17, 2011

There have been concerns that present oxygen levels may limit plant productivity. Swedish researchers at Umea University show that this is not the case in a new study published in the journal The Proceedings of the National Ac ...

Chemists shed light on solar energy storage

Dec 08, 2006

Chemistry's role in bridging the gap between solar energy's limited present use and enormous future potential was the topic of a recent article by MIT Professor Daniel G. Nocera and a colleague.

'Molecular glass fibers'

Apr 26, 2010

Dutch nanotechnologists from the MESA+ research institute of the University of Twente have discovered that the photosynthesis system of bacteria can be used to transport light over relatively long distances. ...

Rhodopsin phototrophy promotes bacterial survival

Apr 27, 2010

Bacteria in the ocean can harvest light energy from sunlight to promote survival thanks to a unique photoprotein. This novel finding by a team of scientists in Sweden and Spain is to be published next week in the online, ...

Fuel from food waste: bacteria provide power

Jul 17, 2008

Researchers have combined the efforts of two kinds of bacteria to produce hydrogen in a bioreactor, with the product from one providing food for the other. According to an article in the August issue of Microbiology Today, this t ...

Recommended for you

Compound from soil microbe inhibits biofilm formation

9 hours ago

Researchers have shown that a known antibiotic and antifungal compound produced by a soil microbe can inhibit another species of microbe from forming biofilms—microbial mats that frequently are medically harmful—without ...

Researcher among best in protein modeling contests

12 hours ago

A Purdue University researcher ranks among the best in the world in bioinformatics competitions to predict protein structure, docking and function, making him a triple threat in the world of protein modeling.

Survey of salmonella species in Staten Island Zoo's snakes

13 hours ago

For humans, Salmonella is always bad news. The bacterial pathogen causes paratyphoid fever, gastroenteritis and typhoid. But for snakes, the bacteria aren't always bad news. Certain species of Salmonella are a natural part ...

A long-standing mystery in membrane traffic solved

Mar 27, 2015

In 2013, James E. Rothman, Randy W. Schekman, and Thomas C. Südhof won the Nobel Prize in Physiology or Medicine for their discoveries of molecular machineries for vesicle trafficking, a major transport ...

User comments : 0

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

Click here to reset your password.
Sign in to get notified via email when new comments are made.