Antibiotic Breakthrough: Scientists Finally Figure Out How Penicillin Kills Bacteria - SciTechDaily

By University of Sheffield.

October 26, 2021.

The mechanism which allows β-lactam antibiotics, including penicillin, to kill MRSA has been revealed for the first time.

An international team of researchers led by the University of Sheffield discovered that β-lactam antibiotics kill MRSA (Methicillin Resistant S. aureus) by creating holes in the cell wall which enlarge as the cell grows, eventually killing the bacteria.

The growth of these holes leads to failure of the cell wall and death of the bacteria, something which the scientists now plan to exploit in order to create new therapeutics for antibiotic-resistant superbugs.

It was previously known that β-lactam antibiotics work by preventing cell wall growth, but exactly how they kill has remained a mystery until now.

Professor Simon Foster, from the University of Sheffield’s School of Biosciences, said: “Penicillin and other antibiotics in its class have been a centerpiece of human healthcare for over 80 years and have saved over 200 million lives.

“Concentrating on the superbug MRSA, our research revealed that the antibiotics lead to the formation of small holes that span the cell wall that gradually enlarge as part of growth-associated processes, eventually killing the bacteria.

The team worked with a simple model for how the bacterial cell wall expands during growth and division and established a hypothesis for what happens when this is inhibited by antibiotics like penicillin.

The project was led by the University of Sheffield as an international, interdisciplinary effort, involving groups at Xiamen University in China, Masaryk University in the Czech Republic, and McMaster University in Canada.

Reference: “Demonstration of the role of cell wall homeostasis in Staphylococcus aureus growth and the action of bactericidal antibiotics” 25 October 2021, Proceedings of the National Academy of Sciences.

October 22, 2021