The search for an Ebola vaccine

Researchers expertly solved the crystal structures of drugs bound to the outer coating of the Ebola virus to pinpoint the regions that are essential for inhibitory activity.

Ebola is a viral disease that is highly infectious and associated with a high risk of death. It first arose in 1976, from which point it was associated with dozens of small-scale outbreaks; however, in 2013 Ebola was responsible for a huge epidemic in West Africa. Emergency was declared and over 11,000 people lost their lives to the virus. Despite this horrific state of affairs, Ebola still remains an untreatable disease and there is no vaccine to prevent infection.

>Read more on the Diamond Light Source website

 

Serial microcrystallography at CHESS

What if large crystals are not available?

The standard X-ray protein crystallography experiment requires a single protein crystal specimen that is large enough to collect a “complete” data set, that is, to collect all the available diffraction peaks to a given resolution.

But what if large crystals are not available? A team of scientists at MacCHESS and the University of Toronto is pushing what is possible for small protein crystals at storage ring sources.

While structural biologists have expanded their purview to increasingly large and complex biological systems, the necessity for reliable, atomic resolution structural data for those systems has not changed. However, it is simply not possible to grow sufficiently large crystals for many systems. The necessity of large crystals in protein crystallography stems primarily from two factors. First, all other things being equal, microcrystals diffract more weakly than large ones, because the crystal volume, and thus number of protein molecules diffracting the X-rays, is lessened. Second, and more insidiously, protein microcrystals succumb more quickly to radiation damage – a loss of diffraction intensity resulting from X-ray induced, stochastic ionization and bond cleavage. These factors result in apparently contradictory solutions: increase the beam intensity to induce more diffraction, but at the expense of crystal lifetime; or lower the beam intensity, but collect weak data.

>Read more on the CHESS website

Image caption: The sample chip loaded and placed on the piezo stage.

Crystallographers identify 1,000 protein structures

The Canadian Light Source is celebrating two milestones reached by scientists who have conducted research at the national facility at the University of Saskatchewan.

Scientists have solved 1,000 protein structures using data collected at CLS’s CMCF beamlines. These have been added to the Protein Data Bank – a collection of structures solved by researchers globally. Researchers have also published 500 scientific papers based on their work using the crystallography beamlines.

Proteins are the building blocks of life and are described as the body’s workhorses. The body is made of trillions of cells. Cells produce proteins, which do the work of breaking down food, sending messages to other cells, and fighting bacteria, viruses and parasites. The discoveries at the CLS range from how the malaria parasite invades red blood cells to why superbugs are resistant to certain antibiotics and how parkin protein mutations result in some types of Parkinson’s disease. Understanding how these and other such proteins work can potentially save millions of lives.

>Read more on the Canadian Light Source website

Image: PDB ID: 6B0S