Modified Antibiotic Fights Antibiotic-Resistant Microbes

Investigators at The Scripps Research Institute (TSRI) in La Jolla, California, may be closer to eliminating the threat of antibiotic-resistant microbes, as they recently discovered a way to structurally modify vancomycin to increase its effectiveness. Led by Dale Boger, PhD, cochair of TSRI’s Department of Chemistry, the team’s discovery pumps more power into an antibiotic that has been prescribed for 60 years — but one for which pathogens are now developing resistance.

This new modification “increases the durability of this antibiotic,” says Boger, whose previous studies showed adding two modifications to the drug makes it even more powerful. Published in Proceedings of the National Academy of Sciences, the study “Peripheral Modifications of [Ψ[CH2NH]Tpg4]Vancomycin With Added Synergistic Mechanisms of Action Provide Durable and Potent Antibiotics,” found that adding a third modification to vancomycin interferes with a bacterium’s cell wall in a novel way. This newly modified version killed both vancomycin-resistant enterococci bacteria, as well as the original forms of enterococci. “Organisms can’t simultaneously work to find a way around three independent mechanisms of action,” he says. “Even if they found a solution to one of these mechanisms, the organisms would still be killed by the other two.”

This discovery means clinicians would need to prescribe less of the antibiotic to fend off infection, according to researchers.

From Decisions in Dentistry. July 2017;3(7):9.