Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Two in One enzyme: unusually flexible

06.10.2008
Scientists from the Ruhr-University Bochum (RUB) have solved the structure of a viral protein

The Journal of Biological Chemistry has ranked this documentation as “Paper of the Week.”

A virus that infects the marine cyanobacterium Prochlorococcus can produce specific pigments more effectively than its host can. It requires only one enzyme, in contrast to the host Prochlorococcus, which needs two enzymes. The virus makes use of phycoerythrobilin synthase, a “two in one” enzyme.

Within the frameworks of his dissertation, Thorben Dammeyer, a member of the research team under the supervision of Prof. Nicole Frankenberg-Dinkel (Physiology of Microorganisms) and Assistant Professor Dr. Eckhard Hofmann (X-ray diffraction analysis of proteins), solved the 3D structure of the enzyme. An unexpected flexibility was discovered, allowing sections of the protein to assume different positions – an unusual property for proteins in combination with their substrate. The scientists have documented their results, honored as “Paper of the Week,” in the current issue of the Journal of Biological Chemistry.

Pigments are produced in two steps

The so-called P-SSM2 virus with the “two in one” enzyme infects the cyanobacterium Prochlorococcus, a cyanobacterium found in extremely large numbers in the worlds oceans. The virus does however differ in that - in contrast to its cyanobacterial relatives - it does not harvest light for photosynthesis via red and blue pigments, but with chlorophyll, as is the case with higher plants. Nevertheless Prochlorococcus contains all the genetic information for the entire machinery required to produce these pigments. This takes place in two steps with two different enzymes as catalysts.

Green turns red in one step

Nicole Frankenberg-Dinkel stated that “we have discovered the genetic blueprint for an enzyme within the virus. This enzyme is capable of producing the red pigment more effectively than its host, which has convinced us that the pigment cannot be unimportant for Prochlorococcus, even if it is not required for light trapping. On the other hand, we obviously wanted to know how this enzyme can combine two functions.” The scientists used X-ray diffraction analysis to determine the 3D structure of the enzyme at atomic resolution both alone and in complex with its natural substrate, the green biliverdin IXa. This molecule was found in the binding pocket of the protein, where the conversion into a red pigment takes place. Prof. Frankenberg-Dinkel explained that the scientists were able to observe how different parts of the enzyme around the binding pocket are capable of assuming different positions. “This property might not be unusual for proteins in solution, but is extremely rarely found in protein crystals.” The structural variations observed supplied the scientists with the first indications of the movements of the enzyme during catalysis.

Next step: tracking the evolution

The next stage of research will consist of studies of targeted and randomly genetically altered forms of the unusually flexible protein. Using this system, the scientists want to observe the in vitro evolution of this specific enzyme. Nicole Frankenberg-Dinkel’s and Eckhard Hofmann’s research teams are funded by the Collaborative Research Centre 480 “Molecular Biology of Complex Functions in Botanical Systems.”

Prof. Dr. Frankenberg-Dinkel | alfa
Further information:
http://www.rub.de/sfb480

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>