Researchers at Florida State University have developed a 3D model that examines how the bacterium Helicobacter pylori moves through viscous fluids. H. pylori can cause gastrointestinal ulcers and even cancer, moving through the intestinal mucus layer to reach the wall of the gut. Using antibiotics can cause side-effects and can contribute to drug resistance, so these researchers are studying how the bacterium navigates through mucus in an effort to find new therapeutic targets with which to disrupt its activity. The researchers constructed models of the bacteria, placed them in a high-viscosity polymer gel, and then emulated their movement to learn more.
H. pylori is found in the gut, where it can cause problems ranging from ulcers to cancer. Simply treating it with antibiotics can work, but it can be difficult to eradicate, and the treatment can produce side-effects. Moreover, finding alternatives to antibiotics is in our long-term interest, given the ongoing development of drug resistance.
These researchers are modelling the motility of H. pylori as it traverses the mucus layer of the gut, a key step in its pathogenic activity, and one that may offer therapeutic targets if we can understand it a little better. The bacterium has a corkscrew shaped tail that it uses for propulsion through viscous substances.
“People around the world have treated ulcers with antibiotics because antibiotics kill bacteria, but it’s a double-edged sword,” said Hadi Mohammadigoushki, a researcher involved in the study. “If we understand how these bacteria move, we can work toward providing other solutions for treatment.”
To achieve this, the researchers constructed a model bacterium and placed it into a high-viscosity polymer gel, as a surrogate for intestinal mucus. They then used a magnetic field to rotate the model, creating a realistic H. pylori style corkscrew movement, and used tracking and imaging techniques to characterize the movements.
“We found that if the tail propulsion was too weak, the bacteria remain stuck in the gel,” said Mohammadigoushki. “If the force was strong enough it could penetrate the gel. It’s kind of like when you are drilling a screw into a solid wall. If your drill isn’t strong enough and you are not pushing the screw with enough force, it won’t penetrate the wall, but with the right amount of force, it can break through.”
“If we understand how the bacteria successfully move to attack our body, we can use that information for whatever we can imagine,” added Kourosh Shoele, another researcher involved in the study.
Study in journal Physical Review Letters: Helical Locomotion in Yield Stress Fluids