Abstract
Glycolysis is a major cytosolic pathway that provides cellular ATP. In eukaryotes, mitochondria play an even more important role in ATP production. Here, we show that the second half of glycolysis is localised to the mitochondria of the stramenopiles (heterokonts). This is a large group of ecologically important eukaryotes that includes multi- and unicellular algae such as kelp and diatoms, but also economically important oomycete pathogens such as Phytophthora infestans. The six last glycolytic enzymes contain mitochondrial targeting signals that are sufficient to target GFP into mitochondria of a heterologous host. Confocal immunomicroscopy confirmed the mitochondrial location of glycolytic enzymes for the human parasite Blastocystis. Enzyme assays on cellular fractions confirmed the presence of these enzymes in Blastocystis mitochondria. These activities are sensitive to treatment with proteases and Triton X-100 but not proteases alone clearly indicating the genuine mitochondrial nature of these enzymes. Our work clearly shows that core cellular metabolism is more plastic than imagined and suggests new strategies to combat stramenopile pathogens such as the causative agent of late potato blight, P. infestans.
