Notre Dame chemist sheds new light on antibiotics and the survival of bacteria | News | Notre Dame News | University of Notre Dame Skip To Content Skip To Navigation Skip To Search University of Notre Dame Notre Dame News Experts ND in the News Subscribe About Us Home Contact Search Menu Home › News › Notre Dame chemist sheds new light on antibiotics and the survival of bacteria Notre Dame chemist sheds new light on antibiotics and the survival of bacteria Published: April 26, 2011 Author: Marissa Gebhard Research in the laboratory of Shahriar Mobashery in the University of Notre Dame’s Department of Chemistry and Biochemistry has led to further understanding of how a bacterial cell wall cross-links, an event that penicillin and other antibiotics disrupt, a step in the maturation of a cell wall that is critical for the survival of bacteria. Mobashery is the Navari Family Chair in Life Sciences at Notre Dame. His group published the findings recently in the Journal of the American Chemical Society in an article titled, “A Computational Evaluation of the Mechanism of Penicillin-Binding Protein-Catalyzed Cross-Linking of the Bacterial Cell Wall.” This very process is the step in maturation of a cell wall that penicillin and other members of the ß-lactam class of antibiotics, the most commonly used antibacterial agents, interfere with. Scientists since the 1940s have worked to explain the antibiotic properties of penicillin, and research had shown that the drug interferes with the cell wall cross-linking, one of the final steps in the maturation of the cell wall. The interference by penicillin leads to points of weakness in the cell wall. Since bacteria cannot regulate their internal osmotic pressure, the action of the drug on the cell wall leads to bacterial death by bursting of the cell. Five years ago, Mobashery’s lab determined the solution structure of the building units of the cell wall, also known as the peptidoglycan. This solution structure for the peptidoglycan was used in the present study in conjunction with a crystal structure determined by a French group for a transpeptidase, the enzyme that catalyzes the cross-linking reaction. The new research shows how the enzyme unites two fragments of the peptidoglycan in the critical cross-linking reaction of the cell wall. “The current paper addresses the physiological function of the enzyme that penicillin inhibits,” Mobashery said. “It opens up opportunities to rethink the process of inhibition. You have the knowledge of how the cell wall cross-linking takes place and you can now mimic it. It has shed light on what I would consider to be a marvel of nature.” Mobashery has a recent NIH grant for five years to study the maturation of the bacterial cell wall, building on the discoveries in the article and other research that is ongoing in his lab. The mature cross-linked cell wall is a single molecule, the largest molecule in bacteria, larger than the bacterial chromosome. Since it is known that a single bacterium contains tens of thousands of these cross-links and that the reaction is the step inhibited by penicillin, the present study illuminates an important aspect of bacterial physiology. Contact: Shahriar Mobashery, 574-631-2933, mobashery@nd.edu Posted In: Research Home Experts ND in the News Subscribe About Us Related October 05, 2022 Astrophysicists find evidence for the presence of the first stars October 04, 2022 NIH awards $4 million grant to psychologists researching suicide prevention September 29, 2022 Notre Dame, Ukrainian Catholic University launch three new research grants September 27, 2022 Notre Dame, Trinity College Dublin engineers join to advance novel treatment for cystic fibrosis September 22, 2022 Climate-prepared countries are losing ground, latest ND-GAIN index shows For the Media Contact Office of Public Affairs and Communications Notre Dame News 500 Grace Hall Notre Dame, IN 46556 USA Facebook Twitter Instagram YouTube Pinterest © 2022 University of Notre Dame Search Mobile App News Events Visit Accessibility Facebook Twitter Instagram YouTube LinkedIn