Scripps researchers add power to antibiotic vancomycin, giving it a third mechanism to fight superbugs
The emergence of antibiotic-resistant bacteria is a major worldwide concern for healthcare professionals worldwide, who in some cases, have been rendered powerless to help patients survive superbug infections that have out-evolved existing drugs. Progress has slowed on creating new antibiotics over several decades as many companies calculated their return on investment for developing one won’t be sufficient, at least without special incentives. According to the World Health Organization, “Without urgent action, we are heading for a post-antibiotic era, in which common infections and minor injuries can once again kill.”
Researchers at The Scripps Research Institute in La Jolla, California have a new plan to prevent that from happening.
In a study published yesterday in the journal Proceedings of the National Academy of Sciences, Dale Boger, co-chair of TSRI’s Department of Chemistry, started with vancomycin, an existing antibiotic that has stood up better than most to the growth of antibiotic resistance. The drug kills bacteria by preventing the cells from building cell walls. After being prescribed for over 60 years, very few of the organisms have managed to resist its curative powers. However, some dangerous strains of gram-positive bacteria, such as Enterococci, which was listed as a high priority by WHO back in February, have recently managed to evolve to evade the drug’s influence.
Boger has been working on modifying and strengthening the drug for several years. In the current study, he has introduced a third modification which makes the drug one thousand times more potent than it is in its original structure. The new formulation kills bacteria using three separate mechanisms, making it highly unlikely that a bacterium would evolve to dodge all three simultaneously. In the study, the drug was effective in killing Enterococci in both its original and vancomycin-resistant forms.
The drug still has a long way to go before doctors will be able to prescribe it though. It takes 30 steps to properly synthesize the molecule the team has designed. It won’t be ready for human trials until it can be synthesized more practically, but Boger describes this step as the “easy part.”