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

High-speed Snapshots of Biomolecules

Published: Friday, May 30, 2014
Last Updated: Tuesday, June 03, 2014
Bookmark and Share
PETRA III pioneers protein serial crystallography at synchrotrons.

Using DESY's synchrotron light source PETRA III, scientists have pioneered a new way to analyse delicate biomolecules. The novel approach, borrowed from a new class of high-intensity X-ray sources called free-electron lasers (FELs), could reveal the atomic structure of proteins that were previously inaccessible to synchrotrons, as the team led by Prof. Henry Chapman from the Hamburg Center for Free-Electron Laser Science CFEL reports in the scientific journal of the International Union of Crystallography, IUCrJ. CFEL is a joint institution of DESY, the University of Hamburg and the Max Planck Society.

The atomic structure of biomolecules can reveal the mechanisms underlying their function in the organism, leading to improved biological insight with the potential to enable the development of new medicines. The standard technique for elucidating the atomic structure of proteins involves shining a bright beam of X-rays onto a protein crystal. The crystal scatters the X-rays in a characteristic way, and from the resulting diffraction pattern the inner structure of the crystal can be calculated, yielding the atomic structure of the protein.

"But being jammed into a crystal is not a natural state for most biomolecules, so, many proteins form only very tiny crystals," says DESY scientist Chapman,who is also a professor at the University of Hamburg and a member of the Hamburg Center for Ultrafast Imaging CUI. “The smaller the crystal, the brighter the X-ray light has to be in order to produce usable diffraction patterns.”

Free-electron X-ray lasers can analyse crystals even smaller than one micrometre across, but a single X-ray pulse vaporises the sample after giving a single snapshot. Measurements are made from many tens of thousands of samples in quick succession, and then processed with high performance computers. Synchrotrons on the other hand can determine the atomic structure from just a single crystal, but it has to be large enough and of high quality to be able to rotate it through the beam and explore it from all angles. Often, a handful of high-quality crystals is used.

"We noticed at the X-ray laser that some of the samples were large enough and diffracting quite well, so that we sometimes even had to attenuate the beam so as not to burn the detector," explains first author Dr. Francesco Stellato from CFEL. "So moving the quick-succession FEL method to a bright synchrotron could maybe serve to close a size gap for samples that are too small for conventional synchrotron investigations and sort of too large for free-electron lasers."

To test their hypothesis, the scientists used a well-studied protein called lysozyme and grew micrometre-sized crystals of it. At PETRA III, currently the most brilliant synchrotron light source in the world, they took FEL-style high-speed snapshots of many tiny lysozyme crystals and combined them. “We let a small stream of microcrystals run across the X-ray beam and shot a series of pictures as fast as the detector would allow,” illustrates CFEL scientist Dr. Dominik Oberthür from the team.

The lysozyme crystals were fed as a suspension in water through a thin capillary across the nine micrometre wide X-ray beam. This technique works at room temperature, avoiding the need to deep-freeze the protein crystals. The flow speed was adjusted so that individual microcrystals would not suffer significant radiation damage during the passage. The transit time of the microcrystals across the beam was between one and three milliseconds. “We set the detector on rapid fire, taking 25 pictures per second,” says co-author Dr. Alke Meents, head of the measuring station P11, where the experiments took place.

Almost 1.5 million detector frames were acquired over about 17 hours of experimental time. Automated analysis routines sorted through all the frames to find the 40,233 diffraction patterns hidden amongst them, which were then combined for structural analysis. This yielded the lysozyme structure with a resolution of 2.1 Ångström, or 0.2 millionths of a millimetre and in excellent agreement with known structural data. “With planned improvements on brightness and detectors, even faster images can be recorded, increasing the spatial resolution,” underlines Meents. “This way, our work paves the way for structural analysis of biomolecules previously inaccessible by synchrotrons.”


Further Information

Join For Free

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 3,500+ scientific posters on ePosters
  • More than 5,000+ 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 TechnologyNetworks.com 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.


Scientific News
Antibodies Block Norovirus’ Entrance into Cells
Scientists have uncovered a mechanism in the human body that targets and successfully blocks noroviruses.
Protein Findings Could Lead To New Class Of Antibiotics
Atomic-level images of a protein have revealed a characteristic that could form a basis of new antibiotic approach.
Worms Point Way Toward Viral Strategies
Rice University wins NIH grant to study how nematodes handle gastrointestinal viruses.
'Missing Evolutionary Link' of a Widely Used Natural Drug Source Found
A well-known family of natural compounds, called “terpenoids,” have a curious evolutionary origin. In particular, one question relevant to future drug discovery has puzzled scientists: exactly how does Nature make these molecules?
Mechanisms of Calcium Blockers
Researchers describe how the fundamental mode of action of two distinct chemical classes of calcium channel blockers differs.
Catching Proteins in the Act
Scientists can now observe light activated processes in proteins through the use of free-electron x-ray lasers.
'Missing Evolutionary Link' of Natural Drug Source Found
Scripps Florida study finds 'missing evolutionary link' of a widely used natural drug source
New Way of Displaying 3D Molecular Structures
Metal-organic frameworks provide a new platform for solving the structure of hard-to-study samples.
How Cloud Connectivity Can Combat the Reproducibility Crisis
This infographic explains the reproducibility crisis, and how cloud connectivity can help overcome this problem.
Blocking the Waste Disposal Unit
Detailed structure paves the way for more effective cancer therapies.
SELECTBIO

SELECTBIO Market Reports
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
3,500+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
5,000+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!