Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Energy-saving chaperon Hsp90: Large conformational changes without ATP consummation

With their specially designed three-color single-molecule FRET (Foerster resonance energy transfer) assay with alternating laser excitation (ALEX) for simultaneous observation of ATP binding and conformational changes professor Hugel and his team could prov, that Hsp90 utilizes thermal fluctuations for its large conformational changes.

Credit: Christoph Ratzke
With their specially designed three-color single-molecule FRET (Foerster resonance energy transfer) assay with alternating laser excitation (ALEX) for simultaneous observation of ATP binding and conformational changes professor Hugel and his team could prov, that Hsp90 utilizes thermal fluctuations for its large conformational changes.

Credit: Christoph Ratzke

Abstract:
A special group of proteins, the so-called chaperons, helps other proteins to obtain their correct conformation. Until now scientists supposed that hydrolyzing ATP provides the energy for the large conformational changes of chaperon Hsp90. Now a research team from the Nanosystems Initiative Munich could prove that Hsp90 utilizes thermal fluctuations as the driving force for its conformational changes. The renowned journal PNAS reports on their findings.

Energy-saving chaperon Hsp90: Large conformational changes without ATP consummation

Muenchen, Germany | Posted on January 14th, 2012

ATP is the major energy source for most organisms and ATPases are the machines, which utilize this fuel, for example to move muscles or cargo in our body. The very abundant chaperone protein Hsp90 has such an ATPase in each of its two monomers. During the last years experiments had suggested that the movement and conformational changes of ATPase proteins are in general strictly linked to ATP binding and hydrolysis (i.e. fuel consumption).

To probe this theory Thorsten Hugel, Professor at the Technische Universitaet Muenchen (TUM) and member of the Nanosystems Initiative Munich (NIM), and his team designed a special three color single-molecule FRET (Förster resonance energy transfer) assay with alternating laser excitation (ALEX) for simultaneous observation of ATP binding and conformational changes. Unexpectedly the experiments revealed that binding and hydrolysis of ATP is not correlated with the large conformational changes of Hsp90. Hsp90 is instead a highly flexible machinery driven by thermal fluctuations.

"Thermal fluctuations are random changes in the structure of the protein - they can be thought of as collisions with water molecules in the environment, which move rather violently at the temperatures in a living organism," says Thorsten Hugel. "Using these clashes to switch back and forth between different conformations, saves Hsp90 valuable ATP." But then what is the task of ATPase in the Hsp90 chaperone? The scientists suspect that co-chaperones and substrate proteins alter the system so that ATP binding or hydrolysis can take a crucial task.

With the newly developed experimental setup, it is now possible to investigate the very complex system in greater detail to resolve this important question. The Munich biophysicists therewith offer a new perspective on the energy conversion in molecular machines.

The work was supported by grants from the DFG (Hu997/9-1, SFB 863) and the Cluster of Excellence Nanosystems Initiative Munich (NIM) and the NanoBio-Technology program of the Elite Network of Bavaria.

Original publication:

Heat shock protein 90's mechano-chemical cycle is dominated by thermal fluctuations
Christoph Ratzke, Felix Berkemeier, and Thorsten Hugel,
PNAS, January 3, 2012 vol. 109, no. 1, 161-166 - Doi: 10.1073/pnas.1107930108

####

For more information, please click here

Contacts:
Dr. Andreas Battenberg

49-892-891-0510

Copyright © Technische Universitaet Muenchen

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Gold nanoparticle chains confine light to the nanoscale October 31st, 2014

'Nanomotor lithography' answers call for affordable, simpler device manufacturing October 31st, 2014

Device invented at Johns Hopkins provides up-close look at cancer on the move: Microscopic view of metastasis could give insight about how to keep cancer in check October 31st, 2014

Molecular Machines

'Nanomotor lithography' answers call for affordable, simpler device manufacturing October 31st, 2014

Crystallizing the DNA nanotechnology dream: Scientists have designed the first large DNA crystals with precisely prescribed depths and complex 3D features, which could create revolutionary nanodevices October 20th, 2014

Optimum inertial design for self-propulsion: A new study investigates the effects of small but finite inertia on the propulsion of micro and nano-scale swimming machines July 29th, 2014

Breakthrough laser experiment reveals liquid-like motion of atoms in an ultra-cold cluster: University of Leicester research team unlocks insights into creation of new nano-materials July 25th, 2014

Nanomedicine

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Production of Biocompatible Polymers in Iran October 30th, 2014

Amorphous Coordination Polymer Particles as alternative to classical nanoplatforms for nanomedicine October 30th, 2014

'Electronic skin' could improve early breast cancer detection October 29th, 2014

Discoveries

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Gold nanoparticle chains confine light to the nanoscale October 31st, 2014

'Nanomotor lithography' answers call for affordable, simpler device manufacturing October 31st, 2014

Device invented at Johns Hopkins provides up-close look at cancer on the move: Microscopic view of metastasis could give insight about how to keep cancer in check October 31st, 2014

Announcements

Nano Ruffles in Brain Matter: Freiburg researchers decipher the role of nanostructures around brain cells in central nervous system function October 31st, 2014

Gold nanoparticle chains confine light to the nanoscale October 31st, 2014

'Nanomotor lithography' answers call for affordable, simpler device manufacturing October 31st, 2014

Device invented at Johns Hopkins provides up-close look at cancer on the move: Microscopic view of metastasis could give insight about how to keep cancer in check October 31st, 2014

Tools

Device invented at Johns Hopkins provides up-close look at cancer on the move: Microscopic view of metastasis could give insight about how to keep cancer in check October 31st, 2014

A new cheap and efficient method to improve SERS, an ultra-sensitive chemical detection technique October 28th, 2014

New Compact SIMS at 61st AVS | Visit us on Booth 311 October 28th, 2014

New nanodevice to improve cancer treatment monitoring October 27th, 2014

Photonics/Optics/Lasers

Gold nanoparticle chains confine light to the nanoscale October 31st, 2014

Watching the hidden life of materials: Ultrafast electron diffraction experiments open a new window on the microscopic world October 27th, 2014

Physicists build reversible laser tractor beam October 20th, 2014

Magnetic mirrors enable new technologies by reflecting light in uncanny ways October 16th, 2014

NanoNews-Digest
The latest news from around the world, FREE





  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE