Vancomycin is a common antibiotic used to treat gram-positive bacterial infections. It targets a key building block of the bacterial cell wall called Lipid II, but it can’t reach this lipid in gram-negative pathogens because their outer membranes block such large molecules. Now, chemists at the Shanghai Institute of Materia Medica, Chinese Academy of Sciences have found that
attaching a small quinoline group to vancomycin lets it slip inside the bacteria and reach its target (
J. Am. Chem. Soc. 2025, DOI: 10.1021/jacs.5c14268).
While the team originally added the quinoline to boost vancomycin’s activity against resistant gram-positive bacteria, several of the modified molecules unexpectedly killed the multidrug-resistant gram-negatives
Escherichia coli and
Salmonella. They also worked better against stubborn gram-positive superbugs like methicillin-resistant
Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci.