Corporate Banner
Satellite Banner
Biomolecular Screening
Scientific Community
Become a Member | Sign in
Home>News>This Article

Major Advance in Human Proteins

Published: Monday, December 23, 2013
Last Updated: Monday, December 23, 2013
Bookmark and Share
The paper, “Serial femtosecond crystallography of G-protein-coupled receptors,” reports the successful imaging, at room temperature, of the structure of GPCR with the use of an x-ray free-electron laser.

A group of researchers from Arizona State University are part of a larger team reporting a major advance in the study of human proteins that could open up new avenues for more effective drugs of the future. The work is being reported in this week’s Science magazine.

GPCR’s are a highly diverse group of membrane proteins that mediate cellular communication. Because of their involvement in key physiological and sensory processes in humans, they are thought to be prominent drug targets.

The method described in the paper was applied for the first time to this important class of proteins, for which the 2012 Nobel Prize was awarded to Brian Kobilka and Robert Lefkowitz, said John Spence, an ASU professor of physics. Spence is also the director of science at National Science Foundation’s BioXFEL Science and Technology Center, and a team member on the Science paper.

“These GPCR’s are the targets of a majority of drug molecules,” Spence said, but they are notoriously difficult to work with. This is the first time structural observations of the GPCR’s have been made at room temperature, allowing researchers to overcome several disadvantages of previous imaging methods of the proteins.

“Normally, protein crystallography is performed on frozen samples, to reduce the effects of radiation damage,” Spence said, “but this new work was based on an entirely new approach to protein crystallography, called SFX (Serial Femtosecond Crystallography), developed jointly by ASU, the Deutsches Elektronen-Synchrotron (DESY) and the SLAC National Accelerator Laboratory.

“This method uses brief pulses of x-rays instead of freezing the sample to avoid damage, and so it reveals the structure which actually occurs in a cell at room temperature, not the frozen structure,” Spence added. “The 50 femtosecond pulses (120 per second) ‘outrun’ radiation damage, giving a clear picture of the structure before it is vaporized by the beam.”

The femtosecond crystallography technique could enable researchers to view molecular dynamics at a time-scale never observed before. Spence said the method basically operates by collecting the scattering for the image so quickly that images are obtained before the sample is destroyed by the x-ray beam.

By "outrunning" radiation-damage processes in this way, the researchers can record the time-evolution of molecular processes at room temperature, he said.

Spence said ASU played a crucial role in the project described in Science, through the invention by Uwe Weierstall (an ASU physics professor) of an entirely new device for sample delivery suited to this class of proteins.

The lipic cubic phase (LCP) injector that Weierstall developed replaces the continuous stream of liquid (which sends a continuously refreshed stream of proteins across the pulsed x-ray beam) with a slowly moving viscous stream of ‘lipid cubic phase solution,’ which has the consistency of automobile grease.

“We call it our ‘toothpaste jet,’” Spence said.

He added that the LCP solves three problems associated with previous SFX work, which made this new work possible:

• The viscosity slows the flow rate so the crystals emerge at about the same rate as the x-ray pulses come along, hence no protein is wasted. This is important for the study of human protein, which is more costly than diamond on a per gram basis.

• The “hit rate” is very high. Nearly all x-ray pulses hit protein particles.

• Most important, LCP is itself a growth medium for protein nanocrystals.

“A big problem with the SFX work we have been doing over the past four years is that people did not know how to make the required nanocrystals,” Spence said. “Now it seems many can be grown in the LCP delivery medium itself.”

The international team reporting the advance in Science includes researchers from the Scripps Research Institute, La Jolla, Calif.; the Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany; the Department of Physics and the Department of Chemistry and Biochemistry at ASU, Tempe, Ariz.; SLAC National Accelerator Laboratory, Menlo Park, Calif.; Trinity College, Dublin, Ireland; Uppsala University, Sweden; University of Hamburg, Germany; and Center for Ultrafast Imaging, Hamburg, Germany.

The collaboration between the team at ASU and the research groups at the Scripps Research Institute led by Professor Vadim Cherzov was initiated by Petra Fromme at ASU as a collaboration between two of the membrane protein centers of the Protein Structure Initiative of the National Institute of Health (PSI:Biology) -- the Center for Membrane Proteins in Infectious Diseases (MPID) at ASU and Trinity College Dublin led by  Petra Fromme, and the GPCR Network at Scripps led by Prof. Ray Stevens.

Fromme led the ASU group that helped plan the experiments, characterize the samples and assist with data collection. Other members of the ASU team include Daniel James, Dingjie Wang, Garrett Nelson, Uwe Weierstall, Nadia Zatsepin, Richard Kirian, Raimund Fromme, Shibom Basu, Christopher Kupitz, Kimberley Rendek, Ingo Grotjohann and John Spence.

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,600+ scientific posters on ePosters
  • More than 3,800+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Inflammation Linked to Colon Cancer Metastasis
A new Arizona State University research study led by Biodesign Institute executive director Raymond DuBois has identified for the first time the details of how inflammation triggers colon cancer cells to spread to other organs, or metastasize.
Wednesday, August 26, 2015
Vaccine Technology Takes Dramatic Step Forward
New and increasingly sophisticated vaccines are taking aim at a broad range of disease-causing pathogens, targeting them with greater effectiveness at lower cost and with improved measures to ensure safety.
Wednesday, November 07, 2012
Dissected Brains of Fruit Flies Provide Clues in Autism Research
A new bioassay methodology identifies drugs that may increase the cognitive functionality of children with mental retardation or autism.
Thursday, January 29, 2009
Scientific News
Enzyme Malfunction May be Why Binge Drinking Can Lead to Alcoholism
A new study in mice shows that restoring the synthesis of a key brain chemical tied to inhibiting addictive behavior may help prevent alcohol cravings following binge drinking.
Cell's Waste Disposal System Regulates Body Clock Proteins
New way to identify interacting proteins could identify potential drug targets.
Compound Doubles Up On Cancer Detection
Researchers have found that tagging a pair of markers found almost exclusively on a common brain cancer yields a cancer signal that is both more obvious and more specific to cancer.
Promising Drug Candidate to Treat Chronic Itch
In a new study, scientists from the Florida campus of The Scripps Research Institute (TSRI) describe a class of compounds with the potential to stop chronic itch without the adverse side effects normally associated with medicating the condition.
Are Changes to Current Colorectal Cancer Screening Guidelines Required?
Editorial suggests more research is needed to pinpoint age to end aggressive screening.
Assessing Cancer Patient Survival and Drug Sensitivity
RNA editing events another way to investigate biomarkers and therapy targets.
New Molecular Marker for Killer Cells
Cell marker enables prognosis about the course of infections.
Potential Target for Treatment of Autism
Grant of $2.4 million will support further research.
Sniffing Out Cancer
Scientists have been exploring new ways to “smell” signs of cancer by analyzing what’s in patients’ breath.
Inroads Against Leukaemia
Potential for halting disease in molecule isolated from sea sponges.

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,600+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,800+ scientific videos