Towards mitochondrial metabolomics

Mitochondria are cellular compartments involved in energy and redox control, and as such are key compartments regulating system homeostasis and responses to environmental stimuli. Many metabolites are mediators between different signaling or metabolic pathways, and are produced only under specific environmental stress. Our aim is to study metabolic composition of mitochondria under a variety of environmental and genetic interventios, and link such information to the cell physiology. Initially, we are studying mitochiondria in S. cerevisiae. After isolating mitochondria, we pursue the analysis using LC/MS, GC/MS, and NMR approaches. New computational and statistical methods have been developed and applied to tract subtle changes in spectral data, leading to identification of compounds most descriptive of various physiological responses. As an example, figure shows that even linear dimensionality reduction method such as PCA can separate the metabolites from whole cells and mitochondria, based on 2627 peaks detected using LC/MS, with 140 peaks separating the compartments with p