Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

’Knot’ to be undone, researchers discover unusual protein structure

27.11.2002


Researchers funded by the National Institute of General Medical Sciences have determined the structure of a protein with a surprising feature in it: a knot. This is the first time a knot has been found in a protein from the most ancient type of single-celled organism, an archaebacterium, and one of only a few times a knot has been seen in any protein structure.



This very unusual protein shape finding is a result from the NIGMS Protein Structure Initiative, a 10-year effort to determine 10,000 unique protein structures using fast, highly automated methods. NIGMS, a component of the U.S. Department of Health and Human Services’ National Institutes of Health, provides $50 million per year to nine PSI research centers. The protein knot structure was solved at one of the PSI centers, the Midwest Center for Structural Genomics, which is directed by Andrzej Joachimiak, Ph.D., of Argonne National Laboratory in suburban Chicago.

The researchers describe the new protein structure in the journal Proteins. Their article will be published online Nov. 27 and in print in early December.


"It’s a surprising and different structure," said NIGMS’ John Norvell, Ph.D., director of the Protein Structure Initiative. Protein folding theory previously held that forming a knot was beyond the ability of a protein. Joachimiak suggests that the newly discovered knot may stabilize the amino acid subunits of the protein.

Such discoveries are just what the PSI aims for. "The PSI approach is to solve thousands of unique protein structures," said Norvell. "It’s a discovery-driven effort, a voyage into the unknown. We aren’t sure what we’ll find, but we expect to map a great diversity of protein structures."

"This makes us want to find out why nature goes to the trouble of creating a knot instead of a more typical fold," said Joachimiak.

One of the main goals of the PSI is to understand all of the possible shapes of proteins in nature. Scientists hope that understanding the full range of protein shapes will shed light on the mysterious process proteins use to fold into a three-dimensional structure from a linear chain of amino acid subunits. Ideally, scientists would like to be able to predict the shape of a protein from the sequence of the gene that codes for it. This ability could be immensely useful in understanding diseases and developing new drugs because a protein’s shape offers big clues to its function and can point to ways of controlling that function.

The "high-throughput" PSI approach is radically different from how scientists have approached protein structure determination in the past. Until recently, scientists focused on solving the structures of proteins with known functions.

The newly discovered knotted protein comes from a microorganism called Methanobacterium thermoautotrophicum. This organism is of interest to industry for its ability to break down waste products and produce methane gas. Scientists know which gene codes for the 268-amino acid protein, but they do not know the protein’s function. They speculate that it binds to RNA, a chemical cousin of the genetic material DNA, and helps process this molecule.

The PSI, currently in its pilot phase, expects to move into production phase by the end of 2005. By the end of the pilot phase, each center will aim to produce 100 to 200 new protein structures per year, adding greatly to the number of known structures. The PSI also expects to dramatically lower the average cost of solving a structure.

The paper describing the new structure was authored by scientists at Argonne National Laboratory and the University of Toronto. The nation’s first national laboratory, Argonne conducts basic and applied scientific research across a wide spectrum of disciplines, ranging from high-energy physics to climatology and biotechnology. The laboratory is operated by the University of Chicago as part of the U.S. Department of Energy’s national laboratory system.


NIGMS supports basic biomedical research and training nationwide. NIGMS-funded studies lay the foundation for advances in disease diagnosis, treatment and prevention. To learn more, visit the NIGMS Web site at www.nigms.nih.gov.

For information about the protein knot, contact Linda Joy in the NIGMS Office of Communications and Public Liaison at 301-496-7301 to speak with PSI director John Norvell, Ph.D, or Catherine Foster of Argonne National Laboratory at 630-252-5580 to speak with Andrzej Joachimiak, Ph.D.

REFERENCE

Zarembinski TI, Kim Y, Peterson K, Christendat D, Kharamsi A, Arrowsmith CH, Edwards AM, Joachimiak A. Deep trefoil knot implicated in RNA binding found in an archaebacterial protein. Proteins 2002; 50: 177-183.


Linda Joy | EurekAlert!
Further information:
http://www.nih.gov/nigms

More articles from Health and Medicine:

nachricht Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University

nachricht Direct conversion of non-neuronal cells into nerve cells
03.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>