Scientists break record while battling antibiotic resistance

Drug-resistant diseases could cause up to 10 million deaths a year by 2050, according to the World Health Organization. Scientists used the Canadian Light Source (CLS) at the University of Saskatchewan to better understand how current antibiotics work and how we might curb bacterial resistance to these life-saving drugs.

Many new antibiotics are able to kill infection-causing bacteria by binding to these bacteria’s ribosomes, which are the essential machines that make proteins. In order to see exactly what antibiotics do at an atomic level, researchers from McGill University used the CLS to determine the physical structure of a ribosome as it interacted with one of the newest antibiotics.

To understand how some bacteria are already resistant to this new antibiotic, they also determined how the drug interacts with a key bacterial enzyme that causes the resistance. The results were recently published in Nature Communications Biology.

Visualizing the antibiotic bound to the ribosome, which is a complex with 300,000 atoms, was a feat that took the team roughly five years to complete. In the process, the scientists broke the record for the largest structure ever analyzed using the CMCF beamline at the CLS, which is the only facility of its kind in Canada. The previous record, set in 2013, was for a structure six times smaller.

Read more on the CLS website

Image: Dr Albert Berghuis

Credit: Canadian Light Source

Battling bad bugs

Scientists fight antibiotic resistance by using synchrotron to study scab disease in potatoes.

In the ongoing war against antibiotic resistant bacteria, a change in battle tactics may prove effective for controlling a common disease of plants and potentially other toxins that affect humans and animals.

Although bacterial toxins cause serious, often deadly diseases, “bacteria aren’t trying to be nasty,” said Dr. Rod Merrill, Professor of Molecular and Cellular Biology at the University of Guelph. “They’re hungry and looking for food, and we’re often the food.” He added that 99 per cent of bacteria are helpful – like gut flora – so the battle is against the remaining one per cent.

The usual approach is to develop antibiotics “that kill the bacteria but not us, or the plant, or the animal,” stated Merrill. However, bacteria mutate quickly, as quickly as every 30 minutes, which leads to antibiotic resistance. “And unfortunately, the pipeline for new antibiotics is empty.”

The approach that Merrill and his research group are pursuing is an anti-virulence strategy – finding or designing small molecules that inhibit the tools bacteria use to colonize the host and create infection. “If we can put a lock on their weapons, they can’t get food and will move on so there’s not the same pressure to mutate. We’re going with this approach because we think it’s time to change up tactics.”

Read more on the CLS website

Image: Scabin crystals

Credit: CLS