Researchers Find Parasite 'Kill Switch' Protein
Scientists have identified a protein, PEX38, that acts as a "kill switch" for parasites causing neglected diseases like sleeping sickness and Chagas disease. The protein is crucial for parasite survival but absent in humans, making it a promising and safe target for new drug development.
The newly identified protein, PEX38, is part of a unique metabolic system within the parasites that cause sleeping sickness, Chagas disease, and leishmaniasis. These parasites, known as trypanosomes, have specialized organelles called glycosomes to process sugar for energy, a function that occurs in the cytosol of human cells. Disrupting the formation of these glycosomes is lethal to the parasite, making them a key therapeutic target. This research, led by Professor Ralf Erdmann at Ruhr University Bochum in Germany, marks a significant step forward as PEX38 is the first peroxin—a protein involved in forming these organelles—to be discovered outside of yeast and mammals in over three decades. The discovery of PEX38 offers a highly specific target for new drugs because it is essential for the parasite's survival but does not exist in the human body, minimizing the risk of side effects. The finding is particularly crucial given the limitations of current treatments for these neglected tropical diseases, which are often highly toxic and face increasing parasite resistance. These diseases collectively affect over a billion people worldwide, primarily in impoverished regions. For instance, sleeping sickness is 100% fatal if left untreated, and Chagas disease can lead to life-threatening cardiac and digestive issues years after the initial infection. The PEX38 protein represents an interesting case of evolutionary adaptation. In most organisms, an ancestral version of this protein helps transport proteins to the endoplasmic reticulum. Trypanosomes lost this pathway during their evolution but repurposed PEX38 to transport proteins to their essential glycosomes instead. Researchers are now focused on developing compounds that can disrupt the interaction of PEX38 with other proteins, effectively shutting down the parasite's energy production.
