By changing their shape, some bacteria can grow more resistant to antibiotics

New research led by Carnegie Mellon University’s assistant professor of physics, Shelditia Banerjee, demonstrates how certain types of bacteria can adapt to long-term exposure to antibiotics by changing their shape. The work has been published in the journal Nature Physics.

Adaptation is a basic biological process that drives organisms to change their traits and behavior to better suit their environment, whether it be the famous diversity of sparrows observed by pioneering biologist Charles Darwin or many species of birds. bacteria That humans coexist with. While Antibiotics As long as people help prevent and treat bacterial infections, many types of bacteria are increasingly able to adapt to resistance. Antibiotic treatments.

Banerjee’s research at Carnegie Mellon University and in his previous position at University College London (UCL) focused on the mechanics and physics behind different cellular processes, and the common theme in his work was that cell shape can have significant impacts on its reproduction and survival. Together with researchers at the University of Chicago, he decided to investigate how antibiotic exposure affects the growth and morphology of Caulobacter crescentus, a commonly used bacterium. Model object.

“By using single-cell experiments and theoretical modeling, we demonstrate that cell morphology changes act as a feedback strategy to make bacteria more adapted to the remaining antibiotics,” Banerjee said of what he and his colleagues found.

Upon exposure to lower than lethal doses of the antibiotic chloramphenicol over several generations, researchers found that the bacteria changed their shape dramatically by becoming wider and more curved.

“These changes in morphology enable the bacteria to overcome antibiotic stress and resume rapid growth,” Banerjee said. The researchers came to this conclusion by developing a theoretical model to show how this happened Physical changes It allows bacteria to achieve higher curvature and a lower surface-to-volume ratio, which allows fewer antibiotic particles to pass through their cell surfaces as they grow.

“This insight has a huge impact on human health and is likely to motivate more Molecular studies In the role of the cell Form On bacterial growth and antibiotic resistance, Banerjee said.

Other authors on the study include Aaron R Dinner, Clevin Law, and Norbert F. Scherer of the University of Chicago. Nikola Ojkich and Rosen Stevens are former members of the Banerjee Research Group at the University of California.