To analyze the movement of germs, researchers utilize 3D models.

The common and problematic bacteria Helicobacter pylori has a spiral shape.

The prevalence of H. pylori infection varies by age, race, and socioeconomic status, but it affects more than 13% of Americans. The microorganism propels itself forward through viscous fluids like stomach mucus with its tail, which resembles a corkscrew. It can cause anything from ulcers to cancer when it reaches the epithelium of the stomach wall.

Researchers from the FAMU-FSU College of Engineering created a 3D model of this bacteria for a new study that was published in Physical Review Letters. The goal of the study was to gain a better understanding of the organism’s movement, crack the code that governs the organism’s motility, and develop alternative treatments for infections, such as strengthening the gastric mucus barrier that protects the body from the bacteria.

“Antibiotics have been used to treat ulcers all over the world because they kill bacteria, but it’s a two-edged sword.”

Study co-author Hadi Mohammadigoushki,

“Antibiotics have been used to treat ulcers around the world because they kill bacteria,” said study co-author Hadi Mohammadigoushki, an associate professor in the Department of Chemical and Biomedical Engineering. “But it’s a double-edged sword.” Assuming we comprehend how these microscopic organisms move, we can make progress toward giving different answers for treatment.”

Credit: Hadi Mohammadigoushki

a clip of the 3D model swimming through gel in the video.

In the experiments, the team placed a model of the bacteria in a yield-stress fluid, a high-viscosity polymer gel. Those liquids act as solids under little burdens yet stream like fluids past a basic emphasize point.

The 3D model was then rotated by means of a magnetic field to resemble the microorganism’s behavior. The researchers measured the bacteria’s speed and observed the fluid’s distribution and density using particle tracking and imaging methods.

The bacteria must overcome two critical thresholds, according to the researchers: the force required to move the swimming model forward and the torque required to rotate the model.

“We viewed that as in the event that the tail drive was too frail, the microscopic organisms would stay caught in the gel,” Mohammadigoushki said. “It could break through the gel if the force was strong enough. This is similar to drilling a screw into a solid wall. In the event that your drill isn’t sufficient and you are not pushing the screw with sufficient power, it will not enter the wall; however, with the perfect proportion of power, it can get through.”

The helical swimmer was activated in this study by a custom-made rotating Holmholtz coil. The angular velocity of this apparatus is constant. The various planes that can be used for analysis around the swimmer are depicted in the shaded green zones. Credit: Hadi Mohammadigoushki

The force and swimming motions that enable H. pylori to move also apply to larger organisms, such as earthworms that dig a hole in the ground and a variety of parasites, among other things.

Kourosh Shoele, an assistant professor in the Department of Mechanical Engineering, stated, “We can use that information for whatever we can imagine if we understand how the bacteria successfully move to attack our body.”

Shoele is important for the multidisciplinary research group and is a specialist in computational science. He talked about how learning from nature can help mechanical and biological systems respond better.

Kourosh Shoele, an associate teacher of mechanical design; Hadi Mohammadigoushki, an academic partner in compound and biomedical design; and Farshad Nazarinasrabad, a doctoral up-and-comer in synthetic design at the FAMU-FSU School of Designing. Credit: Mark Wallheiser/FAMU-FSU College of Engineering.

“In the future, we can design a micro-robot that can deliver a drug to a particular location in the body, in terms of fighting leukemia and other diseases,” Shoele stated. Mark Wallheiser/FAMU-FSU College of Engineering Or, as with H. pylori, we might create tiny robots that can explore the sand for oil or water by swimming and using force. There is no end to the possibilities.”

Together with the two researchers, Farshad Nazari, a doctoral student at FSU in chemical and biomedical engineering, is a co-author of this paper.

More information: Farshad Nazari et al, Helical Locomotion in Yield Stress Fluids, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.130.114002

Topic : Article