Scientists develop new method to identify glycosylated proteins

May 27, 2010
Ionization of the sample with electro spray prior to the mass spectrometer measurement. Image: Axel Griesch

(PhysOrg.com) -- Various processes in our body are controlled by subsequent changes of proteins. Therefore, the identification of such modifications is essential for the further exploration of our organism. Now, scientists of the Max Planck Institute of Biochemistry in Martinsried, Germany, have made a crucial contribution to this: Using a new method, they have been able to identify more than 6,000 glycosylated protein sites in different tissues and have thus established an important basis for the better understanding of all life processes (Cell, May 28, 2010)

Many biological mechanisms like , apoptosis or pathogenesis of diseases are based on the subsequent transformation of single components of proteins, the . Scientists call this process "posttranslational modification". Although the technologies in proteomics have developed rapidly in the last years, until now the identification of such modified proteins was only possible with limitations.

Particularly, the transformation of proteins by glycosylation - carbohydrates binding to single amino acids - has been widely unexplored. But exactly this process is one of the most important mechanisms for the transformation of proteins and plays an important role in the formation of organs and organisms. When errors occur during the protein modification or in case it takes place in an unregulated way, this can contribute to diseases like Alzheimer’s disease or Creutzfeldt-Jakob disease.

Now, scientists of the Max Planck Institute of in the research department "Proteomics and Signal Transduction", headed by Matthias Mann, have been able to shed light on the dark: They developed a method based on that allows the identification of N-glycosylated protein sites in different tissues in a highly efficient way. N-glycosylation is a specific type of glycosylation, during which the carbohydrates bind on a certain component of a protein, the amino acid asparagine (abbreviated with "N").

The new method is based on a filter technique which offers the possibility to extract also poorly accessible proteins from biological samples. The scientists combined this method with the application of high-resolution mass spectrometers whereby they were able to identify 6,367 N-glycosylated protein sites. Furthermore, they derived novel recognition sequence patterns for N-glycosylation.

These findings constitute an important progress in proteomics, because they help to understand the processes inside of the human body even better. Moreover, they could play an essential role for the investigation of diseases. For example, the scientists managed to identify some modified protein sites which are associated with different illnesses: They discovered N-glycosylated sites, unknown up to now, on proteins which play an important role in Alzheimer’s disease. Because N-glycosylation is involved in many processes which are going wrong in Alzheimer’s disease, scientists suspect that this type of directly causes the disease or, at least, influences its course crucially. Hence, the Max Planck scientists hope that the results of this study could contribute to the further investigation of diseases like Alzheimer’s.

Explore further: Pterostilbene, a molecule similar to resveratrol, as a potential treatment for obesity

More information: D. Zielinska, F. Gnad, J. Wisniewski, M. Mann, Precision Mapping of an In Vivo N-Glycoproteome Reveals Rigid Topological and Sequence Constraints, Cell, May 28, 2010

add to favorites email to friend print save as pdf

Related Stories

One signal elicits thousands of answers

Nov 10, 2006

Cell signaling mechanisms often transmit information via protein modifications, most importantly the reversible attachment of phosphate, the so-called protein phosphorylation. Researchers at the Max Planck Institute of Biochemistry ...

Scientists locate disease switches

Jul 17, 2009

A team of scientists from the University of Copenhagen and the Max Planck Institute in Germany, has identified no less than 3,600 molecular switches in the human body. These switches, which regulate protein functions, may ...

Chemical probes beat antibodies at own game

Apr 26, 2007

A new way of detecting biological structures could help in the fight against disease. The new method, developed by scientists at Oxford University, uses chemistry to assemble proteins into ‘protein probes’ ...

Recommended for you

Why plants don't get sunburn

Oct 29, 2014

Plants rely on sunlight to make their food, but they also need protection from its harmful rays, just like humans do. Recently, scientists discovered a group of molecules in plants that shields them from ...

Viral switches share a shape

Oct 27, 2014

A hinge in the RNA genome of the virus that causes hepatitis C works like a switch that can be flipped to prevent it from replicating in infected cells. Scientists have discovered that this shape is shared by several other ...

'Sticky' ends start synthetic collagen growth

Oct 27, 2014

Rice University researchers have delivered a scientific one-two punch with a pair of papers that detail how synthetic collagen fibers self-assemble via their sticky ends.

Cell membranes self-assemble

Oct 27, 2014

A self-driven reaction can assemble phospholipid membranes like those that enclose cells, a team of chemists at the University of California, San Diego, reports in Angewandte Chemie.

Emergent behavior lets bubbles 'sense' environment

Oct 27, 2014

Tiny, soapy bubbles can reorganize their membranes to let material flow in and out in response to the surrounding environment, according to new work carried out in an international collaboration by biomedical ...

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.