From the ACS Press Room
Weed-killer Compounds also Kill Parasite sometimes found in Cat Feces pound called heme, is the target of some common herbicides, including oxadiazon. Kerrick Rees, Zhicheng Dou and Daniel Whitehead wondered if these herbicides or their derivatives could kill not only weeds, ACS Infectious Diseases but also T. gondii — without harming human The parasite Toxoplasma gondii infects up to cells. one-third of the human population, experts The researchers screened several herbicides say. Sometimes transmitted to humans from for the ability to kill T. gondii that had infectinfected cat feces or litter, the protozoan can ed human cells in a dish, finding that oxadiacause severe and even deadly illnesses in imzon and a related compound, oxadiargyl, munocompromised people and fetuses. Now, were the most effective. Then, they syntheresearchers reporting in ACS Infectious Dissized 18 derivaeases have discovered that common herbitives of cides and some of their derivatives can kill oxadiargyl that the parasite when it infects human cells in a had different petri dish, without harming the cells themchemical selves. groups at a cerT. gondii infection usually occurs from eating tain region of undercooked contaminated meat, exposure to the molecule, infected cat feces or mother-to-child trans- identifying mission during pregnancy. The parasite caus- some that were es mild or no symptoms in most people, but it even more pocan cause severe illnesses in immunocompro- tent than the mised people and birth defects in the fetuses parent compound. In other experiments, the of pregnant women. Current therapies have researchers confirmed that the herbicide delimitations, such as strong side effects and an rivatives work primarily by inhibiting PPO. inability to cross the placenta to treat the fe- Importantly, the compounds didn’t harm hutus. They also don’t work well for chronic man cells that hosted the parasites. Next, the infections. Recently, scientists discovered researchers plan to test the most potent molethat T. gondii expresses an enzyme cules in an animal model of T. (protoporphyrinogen oxidase, or PPO) that gondii infection. more closely resembles the plant version of The authors acknowledge funding from the the enzyme than the mammalian one. Plant National Institutes of Health. PPO, which helps make an essential com“Oxadiazon Derivatives Elicit Potent Intracellular Growth Inhibition against Toxoplasma gondii by Disrupting Heme Biosynthesis”
May 2022
The Southwest RETORT
13
