A study published in Proceedings of the National Academy of Sciences Reveals the Mechanism that allows beta-lactam antibiotics – which include penicillin – to kill methicillin-resistant ones S. aureus (MRSA) for the first time. Beta-lactam antibiotics were previously known to work by inhibiting cell wall growth, but the exact mechanics remain unknown.
According to the investigators, beta-lactam antibiotics create holes in the cell wall that enlarge as the cells grow and eventually kill the bacteria. The growth of these holes leads to the failure of the cell wall and the death of the bacteria, with which the researchers now want to develop new therapeutics for antibiotic-resistant super bacteria.
“Penicillin and other antibiotics in its class have been at the heart of human health care for over 80 years and have saved over 200 million lives,” said Simon Foster, PhD, in a press release. “However, their use is threatened by the global spread of antimicrobial resistance. Our research focused on the superbug MRSA and showed that the antibiotics lead to the formation of tiny holes that extend across the cell wall that gradually enlarge in growth-associated processes and eventually kill the bacteria. We also identified some of the enzymes involved in making the holes. “
The researchers were able to use this new knowledge and understanding of the control of the enzymes to demonstrate the effectiveness of a novel combination therapy against MRSA. Using a simple model for cell wall expansion in bacteria, they hypothesized what happens when it is inhibited by antibiotics such as penicillin. These predictions were then tested using a combination of molecular approaches, including high resolution atomic force microscopy.
“Our results bring to the heart of our understanding of how existing antibiotics work and give us new avenues for further treatment developments in the face of the global antibiotic resistance pandemic,” Foster said in the press release.
Scientists are making a breakthrough in understanding how penicillin works [news release]. EurekAlert; October 25, 2021. Accessed October 26, 2021. https://www.eurekalert.org/news-releases/932337