Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Chemists make beds with soft landings: Researchers create stable, highly pure helical peptide arrays

With soft-landing techniques, the peptides fashion themselves into stable helices (in red).

Credit: Julia Laskin/Pacific Northwest National Laboratory
With soft-landing techniques, the peptides fashion themselves into stable helices (in red).

Credit: Julia Laskin/Pacific Northwest National Laboratory

Abstract:
Bedsprings aren't often found in biology. Now, chemists have succeeded in making a layer of tiny protein coils attached to a surface, much like miniature bedsprings in a frame. This thin film made of stable and very pure helices can help researchers develop molecular electronics or solar cells, or to divine the biology of proteins.

Chemists make beds with soft landings: Researchers create stable, highly pure helical peptide arrays

RICHLAND, WA | Posted on August 20th, 2008

Physical chemists at the Department of Energy's Pacific Northwest National Laboratory pulled off this design trick using a "soft-landing" technique that disperses the tiny protein coils onto a waiting surface. The small proteins called peptides are of a variety that normally take the shape of a coiled spring or helix in gas phase. The method used by PNNL's Julia Laskin and Peng Wang delivered ultra-pure helical peptides to the surface and trapped them there, they report in July 29 and will appear in print in an upcoming issue of Angewandte Chemie.

"Controlling the conformation of peptides is not easy," said Laskin. "Our previous studies showed that soft-landing can be used to prepare ultrapure peptide layers on substrates. The question we faced was, in addition to controlling purity, can we also control the structure of the molecules? We showed we could."

Researchers have been trying to make thin films of helical peptides for many years. Because the peptides line up in an orderly fashion, the overall chemical nature of the thin films make them useful for a variety of technological applications. They can be modified with light sensitive molecules and turned into components of solar cells; or designed to change shape when a current is applied for molecular electronics. Also, the helices themselves can be used to elicit cues about how proteins function.

After making the thin films out of generic peptides previously, Laskin and Wang wanted to use this method to make a film out of helical peptides, and compare it with a more common method called electrospray.

To do so, Laskin and Wang began with peptides made almost entirely of the amino acid alanine. Due to alanine's chemical nature, long chains of it naturally form so-called α helices. The researchers ended the alanine chain with the amino acid lysine, which stabilizes the helix and allows the coiled chain to be chemically attached to the surface.

Working with a specially designed mass-selected ion deposition instrument at DOE's Environmental Molecular Sciences Laboratory on the PNNL campus, they deposited the peptides on the support layer in one of two ways, starting either from a liquid form for electrospray or from a gaseous mixture for soft-landing. In each case, the chemists began with the peptides (either in liquid or gas), zapped them to give them a slight electrical charge and blew them onto the surface.

When the chemists examined the peptide shapes in the solution and the resulting thin film, they found, unexpectedly, that most of the peptides failed to form helices. Instead, the majority of peptides took on a flat shape known as a β sheet. The dearth of helices in liquid form surprised the researchers.

When the researchers next used soft-landing to form thin layers, they didn't know if the peptides would form helices before landing on the surface. "Because we were starting from something that wasn't α-helical in solution, we were a little pessimistic whether it would work at all," Wang said.

But work it did. Depositing the peptides with soft-landing, the chemists found that nearly all of them alighted as helices. In addition, they could chemically connect the helices to the surface using a related technique called reactive-landing. When the chemists treated the thin layer with sound waves to test how easily the peptides fell off or changed shape, they found that some loosely bound peptides fell off, but those remaining maintained their helical forms.

"They formed a nicely organized, beautiful layer," says Wang.

Next, the team would like to create thin peptide layers using different support surfaces and a different mix of peptide shapes, to learn how to control the design of the thin films precisely.

"We found an interesting pathway to conduct different types of chemical reactions between complex molecules and substrates that will potentially enable us to prepare materials that cannot be made by standard methods," said Laskin.

"We hope to conduct lots of chemistry on the thin films," said Laskin -- chemistry that will let them spring forward into understanding biology and developing new materials.

Reference: P. Wang and J. Laskin, Helical Peptide Arrays on Self-Assembled Monolayer Surfaces through Soft and Reactive Landing of Mass-Selected Ions, Angewandte Chemie, online July 29, 2008, DOI 10.1002/anie.200801366 (dx.doi.org/10.1002/anie.200801366).

This work was supported by PNNL discretionary funding and DOE's Office of Basic Energy Sciences, part of the Office of Science.

The Environmental Molecular Sciences Laboratory is a national scientific user facility sponsored by the Department of Energy's Office of Science, Biological and Environmental Research program that is located at Pacific Northwest National Laboratory. EMSL offers an open, collaborative environment for scientific discovery to researchers around the world. EMSL's technical experts and suite of custom and advanced instruments are unmatched. Its integrated computational and experimental capabilities enable researchers to realize fundamental scientific insights and create new technologies.

####

About DOE/Pacific Northwest National Laboratory
Pacific Northwest National Laboratory is a Department of Energy Office of Science national laboratory where interdisciplinary teams advance science and technology and deliver solutions to America's most intractable problems in energy, national security and the environment. PNNL employs 4,000 staff, has a $855 million annual budget, and has been managed by Ohio-based Battelle since the lab's inception in 1965.

For more information, please click here

Contacts:
Mary Beckman

509-375-3688

Copyright © DOE/Pacific Northwest National Laboratory

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-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Leti and Oscaro Partner on Leti’s New Low-Power, Low-Cost Transceiver to Track Parcels July 12th, 2018

Oxford Instruments’ 22 Tesla superconducting magnet system commissioned at the UAM, making it the most intense magnetic field available outside a large international facility July 12th, 2018

Nanometrics to Announce Second Quarter Financial Results on July 31, 2018 July 12th, 2018

Chemistry

Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides July 13th, 2018

Nanoelectronics

GLOBALFOUNDRIES Surpasses $2 Billion in Design Win Revenue on 22FDX® Technology : With 50 client designs and growing, 22FDX proves its value as a cost-effective solution for power-sensitive applications July 9th, 2018

High-power electronics keep their cool with new heat-conducting crystals July 6th, 2018

Leti Presenting Strategic Vision and Hosting a Workshop at SEMICON West: “From Electrons to Photons” Leti Workshop and CEO Media Briefing Set for Tuesday, July 10 in W Hotel, San Francisco June 12th, 2018

Quantum Interference May Be Key to Smaller Insulators: Breakthrough could jumpstart further miniaturization of transistors June 6th, 2018

Discoveries

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides July 13th, 2018

Researchers identify cost-cutting option in treating nail fungus with nanotechnology: GW researcher Adam Friedman, M.D., studied the potential use of nitric oxide-releasing nanoparticles to improve onychomycosis treatment July 11th, 2018

Announcements

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides July 13th, 2018

Leti and Oscaro Partner on Leti’s New Low-Power, Low-Cost Transceiver to Track Parcels July 12th, 2018

Energy

NIST Researchers Simulate Simple Logic for Nanofluidic Computing June 30th, 2018

Northwestern researchers achieve unprecedented control of polymer grids: Materials could find applications in water purification, solar energy storage, body armor June 22nd, 2018

Physicists devise method to reveal how light affects materials: The new method adds to the understanding of the fundamental laws governing the interaction of electrons and light June 15th, 2018

Tripling the Energy Storage of Lithium-Ion Batteries: Scientists have synthesized a new cathode material from iron fluoride that surpasses the capacity limits of traditional lithium-ion batteries June 14th, 2018

Solar/Photovoltaic

Northwestern researchers achieve unprecedented control of polymer grids: Materials could find applications in water purification, solar energy storage, body armor June 22nd, 2018

Team achieves two-electron chemical reactions using light energy, gold May 15th, 2018

Hematene joins parade of new 2D materials: Rice University-led team extracts 3-atom-thick sheets from common iron oxide May 8th, 2018

Harvesting clean hydrogen fuel through artificial photosynthesis May 3rd, 2018

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



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project