Researchers at the University of Missouri have discovered a compound called MKV3 that may help combat antibiotic-resistant bacteria and certain cancer cells by interfering with how they handle copper. Copper is a vital metal used by many organisms, including humans, to support essential biological processes. The study, published in the Proceedings of the National Academy of Sciences, was led by Vinit Shanbhag, an assistant research professor in the College of Veterinary Medicine, with Michael Petris, a professor of biochemistry, as senior author. Kamal Singh, an assistant professor of veterinary pathobiology, first identified MKV3 using computer modeling techniques. In laboratory experiments, MKV3 was shown to block copper export pumps in harmful bacteria. These pumps normally help bacteria remove excess copper, which can be toxic. By inhibiting these pumps, MKV3 makes bacteria more vulnerable to copper’s damaging effects. This was demonstrated when MKV3 significantly increased the sensitivity of MRSA, a type of antibiotic-resistant bacteria, to copper toxicity. The compound may also have applications in cancer research. Copper is involved in various cellular processes, and recent studies suggest that disrupting copper metabolism could be a way to kill cancer cells. MKV3 increases copper levels inside cancer cells, which can trigger a specific form of cell death known as cuproptosis. It also reduces the activity of an enzyme called lysyl oxidase, which is important for cancer cells to invade surrounding tissues and spread, or metastasize. MKV3 affects copper transport proteins not only in humans but also in other organisms like fungi, plants, fish, and microbes. This is because the compound targets a specific region in copper transporters that is similar across different species. This universality makes MKV3 a useful tool for studying copper transport mechanisms in various biological systems. While the findings are promising, the research is still in its early stages. More studies are needed to fully understand MKV3’s potential and to explore its possible use in medicine. The study was published in the Proceedings of the National Academy of Sciences in 2026.