Startling Images Show How Antibiotic Pierces Bacteria’s Armor

Imagine watching an invisible battle unfold at the microscopic level: tiny warriors dismantling the fortress of a deadly enemy. That's exactly what a team of researchers from University College London (UCL) and Imperial College London has achieved, capturing the first-ever images of how polymyxin antibiotics—a last-resort weapon against superbugs—puncture the tough outer layer of harmful bacteria.

These polymyxins have been a lifeline in hospitals for decades, used to combat infections that laugh off other drugs. But until now, scientists could only theorize about their mechanism. The new study, published in Nature Microbiology, uses advanced cryo-electron microscopy to reveal the process in stunning detail. The images show how the antibiotic molecules latch onto the bacteria's lipopolysaccharide (LPS) armor—the lipid-rich shield that protects Gram-negative bacteria like E. coli and Pseudomonas aeruginosa—and literally tear it apart, creating fatal holes in the cell wall.

This breakthrough comes at a critical time. Antibiotic resistance is one of the world's biggest health threats, causing over 1 million deaths annually and projected to worsen without new strategies. By understanding exactly how polymyxins work, researchers hope to design more effective versions that sidestep resistance mechanisms, ensuring these drugs remain viable longer. Lead author Dr. Anna Wereszczynska from UCL emphasized the human impact: "Seeing this process helps us protect the antibiotics we rely on to save lives."

The findings could pave the way for next-generation treatments, combining polymyxins with other therapies to boost efficacy and reduce side effects. As global health experts warn of a post-antibiotic era, innovations like these offer a glimmer of hope in the fight against microbial foes.

For the full details, check out the original article on Phys.org.