Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rampant helper syndrome

06.07.2009
Methane-producing molecule can also repair DNA

The Archaea are single-celled organisms and a domain unto themselves, quite apart from the so called eukaryotes, being bacteria and higher organisms. Many species live under extreme conditions, and carry out unique biochemical processes shared neither with bacteria nor with eukaryotes.

Methanogenic archaeans, for example, can produce methane gas out of carbon dioxide and hydrogen. The underlying chemical reaction, a reduction, involves the cofactor known as F0 or F420 which is the tiny molecule deazaflavin. It has previously been found only in methanogenic bacteria, and has accordingly been considered the signature molecule for those species.

A research group working with Professor Thomas Carell, however, has now shown that this cofactor is also common in eukaryotes, where it performs an entirely different function: deazaflavin is involved in DNA repair processes. (PNAS Early Edition online, 1 July 2009)

Catalysts assist in chemical reactions without undergoing any alteration of their own. In the cells of living organisms, proteins perform this important function. They carry out the metabolism fundamental to all living processes. Proteins are instrumental in cellular respiration, they for instance reduce oxygen to water and oxidize food into carbon dioxide. This releases the energy that makes life possible at all. Proteins cannot perform these functions on their own. They depend on small helper molecules.

Such molecules are stored inside special pockets in the proteins and carry out essential metabolic functions. The living organism itself produces many of these helpers. Others – like vitamins – must be obtained from food. Severe vitamin deficiencies are a harsh reminder of how essential these molecules are.

Methanogenic bacteria have quite an exceptional task to accomplish: They have to produce methane. In terms of chemistry, this is no mean feat. Methane production is currently one of the most hotly pursued goals for the purposes of renewable energy. It is also a serious greenhouse gas.

Enzymatic methane production involves the tiny molecule deazaflavin, known as cofactor F0 or cofactor F420. This cofactor is stored inside special proteins of methanogenic bacteria, and is essential for methane biosynthesis. Cofactor F0/F420 is a small molecule that, until now, has only been found in methanogenic bacteria. It is regarded as the signature molecule for such species.

"We have now shown that this picture is not entirely true," Carell says. "This cofactor is significantly more widespread in the biosphere than previously assumed. Most importantly, it also occurs in higher organisms, the so-called eukaryotes. But in these, it performs a completely different task." As the researchers were able to demonstrate, the cofactor is involved in DNA repair processes. Specifically, repair of UV damage to the DNA molecule.

Plants and many other organisms that are exposed to intense sunlight must cope with an enormous degree of damage to their genes. To repair those mutations, they need the help of complex enzymes. These photolyases in turn require cofactor FAD – aka vitamin B2 – to accomplish this function. It has long been suspected that these crucial enzymes require yet another cofactor to provide the energy that DNA repair requires.

"We have now shown that, in many organisms, this cofactor is F0/F420," Carell reports. "This molecule has been conclusively detected in DNA repair enzymes of Drosophila melanogaster, the fruit fly. Not long ago, another research group even postulated that F0/F420 is co-responsible for DNA repair in plants. Our view of cofactor F420 as a signature molecule for methanogenic species has therefore radically changed: this cofactor is widespread and it is essential for both methane synthesis and for DNA repair."

Professor Thomas Carell is speaker of the "Center for Integrated Protein Science Munich (CiPSM)" center of excellence which supported this research.

Publication: "The archaeal cofactor F0 is a light-harvesting antenna chromophore in eukaryotes", Andreas F. Glas, Melanie J. Maul, Max Cryle, Thomas R. M. Barends, Sabine Schneider, Emine Kaya, Ilme Schlichting, and Thomas Carell

Contact:
Professor Thomas Carell
Department of Chemistry and Biochemistry
Ludwig-Maximilians-Universität (LMU) München
Phone: +49 (0) 89 / 2180 - 77755 or - 77750
E-Mail:Thomas.Carell@cup.uni-muenchen.de
Web: www.carellgroup.de

Prof Thomas Carell | EurekAlert!
Further information:
http://www.carellgroup.de
http://www.uni-muenchen.de

More articles from Life Sciences:

nachricht Staying in Shape
16.08.2018 | Max-Planck-Institut für molekulare Zellbiologie und Genetik

nachricht Chips, light and coding moves the front line in beating bacteria
16.08.2018 | Okinawa Institute of Science and Technology (OIST) Graduate University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Staying in Shape

16.08.2018 | Life Sciences

Diving robots find Antarctic seas exhale surprising amounts of carbon dioxide in winter

16.08.2018 | Earth Sciences

Protein droplets keep neurons at the ready and immune system in balance

16.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>