Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Flexible neck in cell-receptor DC-SIGN targets more pathogens

New findings from a research team led by University of Illinois chemist Deborah Leckband show that flexibility in the region near the binding sites of DC-SIGN plays a significant role in pathogen targeting and binding.

Photo by L. Brian Stauffer
New findings from a research team led by University of Illinois chemist Deborah Leckband show that flexibility in the region near the binding sites of DC-SIGN plays a significant role in pathogen targeting and binding. Photo by L. Brian Stauffer

Abstract:
Pathogen recognition is the foundation of the body's immune response and survival against infection. A small cell-receptor protein called DC-SIGN is part of the immune system, and recognizes certain pathogens, including those responsible for Ebola, Dengue fever and HIV. How the molecule binds to pathogens has been unclear.

Flexible neck in cell-receptor DC-SIGN targets more pathogens

Champaign, IL | Posted on July 14th, 2009

New findings from a research team led by University of Illinois chemist Deborah Leckband show that flexibility in the region near the binding sites of DC-SIGN plays a significant role in pathogen targeting and binding.

"Our work focuses on how DC-SIGN recognizes HIV and other pathogens, and on what structural features enable it to bind very tightly to those pathogens," said Leckband, the Reid T. Milner Professor of Chemistry at the U. of I. "Once we begin to understand the molecular design rules that lead to this tight binding, we can begin to design inhibitors to block this interaction."

To study the binding behavior of DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin), also known as CD209 (Cluster of Differentiation 209), the researchers used a device called a surface force apparatus.

The surface force apparatus measures the molecular forces between two surfaces as they are first brought together and then pulled apart. In the current work, the surfaces were cell receptor DC-SIGN and a target membrane decorated with carbohydrates to mimic a pathogen surface.

The forces were measured as a function of the distance between the two surfaces, which was measured with single-angstrom resolution (an angstrom is 1 10-billionth of a meter).

"Our force-distance measurements provided the first direct, dynamic evidence for flexibility in the neck of DC-SIGN, and its possible role in pathogen recognition and binding," said Leckband, corresponding author of a paper accepted for publication in the Proceedings of the National Academy of Sciences, and posted on the journal's Web site.

From their force-distance measurements the researchers determined DC-SIGN's neck length as 28 nanometers (a nanometer is 1 billionth of a meter), in agreement with hydrodynamic measurements and theoretical estimates by other researchers, which placed the neck length between 20 and 30 nanometers.

When the protein binds to a pathogen, binding sites on the cell receptor rearrange slightly, to adapt to the target surface and maximize the bond. This 5 nanometer conformational change is binding-induced, and made possible by a flexible linker in the neck, the researchers report.

"The protein neck region acts as a stiff, but flexible, rod that projects the molecule's binding sites away from the cell surface," Leckband said. "A rigid presentation of the binding sites at the end of the neck would restrict DC-SIGN to a few specific, spatial forms. Instead, the molecule's flexibility and adaptability allow it to recognize a much wider range of pathogens."

Co-authors of the paper are graduate student Sindhu Menon and postdoctoral researcher Kenneth Rosenberg at Illinois; and graduate student Sarah Graham, undergraduate student Eliot Ward, senior researcher Maureen Taylor and biochemistry professor Kurt Drickamer at Imperial College, London.

In addition to being a professor of chemical and biomolecular engineering, Leckband also is affiliated with the Beckman Institute, the Institute for Genomic Biology, and the Micro and Nanotechnology Laboratory, all at Illinois.

Funding was provided by the Reid T. Milner Professorship and the Wellcome Trust.

####

About University of Illinois at Urbana-Champaign
We serve the state, the nation, and the world by creating knowledge, preparing students for lives of impact, and addressing critical societal needs through the transfer and application of knowledge.

For more information, please click here

Contacts:
James E. Kloeppel

217-244-1073

Copyright © University of Illinois at Urbana-Champaign

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

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

The 16th Trends in Nanotechnology International Conference (TNT 2015) unveils 25 Keynote Speakers: Call for abstracts open April 27th, 2015

Graphenea celebrates fifth anniversary April 27th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Possible Futures

Printing Silicon on Paper, with Lasers April 21st, 2015

A glass fiber that brings light to a standstill: By coupling photons to atoms, light in a glass fiber can be slowed down to the speed of an express train; for a short while it can even be brought to a complete stop April 9th, 2015

Nanotechnology in Medical Devices Market is expected to reach $8.5 Billion by 2019 March 25th, 2015

Nanotechnology Enabled Drug Delivery to Influence Future Diagnosis and Treatments of Diseases March 21st, 2015

Nanomedicine

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

Nanotech-enabled moisturizer speeds healing of diabetic skin wounds: Spherical nucleic acids silence gene that interferes with wound healing April 24th, 2015

Fast and accurate 3-D imaging technique to track optically trapped particles April 24th, 2015

Announcements

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

The 16th Trends in Nanotechnology International Conference (TNT 2015) unveils 25 Keynote Speakers: Call for abstracts open April 27th, 2015

Graphenea celebrates fifth anniversary April 27th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Nanobiotechnology

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

A silver lining: UCSB researchers cradle silver nanoclusters inside synthetic DNA to create a programmed, tunable fluorescent array April 23rd, 2015

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

UCLA nanoscientists are first to model atomic structures of three bacterial nanomachines: Cryo electron microscope enables scientists to explore the frontiers of targeted antibiotics April 21st, 2015

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