<i>Leishmania</i> (IMAGE) Washington University School of Medicine Caption Scientists at Washington University School of Medicine in St. Louis recently showed that when a key protein was genetically disabled, the parasite Leishmania couldn't start infections in cell cultures and animals. Parasites in this picture have been stained so that compounds known as polyphosphates appear yellow. The structures where the parasite normally stores these compounds are misshapen and empty in mutant parasites that lack the TOR kinase 3 protein. Credit Washington University School of Medicine in St. Louis Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.