VATIS UPDATE Article

A team of scientists from the universities of Freiburg, Homburg, and Rehovot (Israel) led by Prof. Dr. Bettina Warscheid, Prof. Dr. Nikolaus Pfanner, and Prof. Dr. Nils Wiedemann have discovered, counted and determined new mitochondrial proteins with unknown function in the model organism baker’s yeast. The study will serve as a source of information for researchers interested in the biology of mitochondria – from yeast to human subjects. This research was funded through European Research Council (ERC) Consolidator Grants.

Using ‘quantitative mass spectrometry’ and bioinformatics methods, a team from Warscheid’s research group first determined the abundance of thousands of proteins in different cellular fractions of baker’s yeast. A team from Wiedemann’s research group then analyzed mitochondrial proteins using biochemical methods and microscopy. The resulting mitochondrial proteome comprises a total of 901 proteins, including 82 proteins not previously associated with mitochondria.

For an additional 119 a mitochondrial localization had been ambiguous. While humans require oxygen to breathe, yeast cells can either consume oxygen or use a different metabolic pathway called fermentation, a process well known for producing alcoholic beverages. The researchers cultured yeast cells in a fermentative or respiratory medium and determined that the shift from fermentative to respiratory conditions caused dramatic changes in the mitochondria. The study has been published in the scientific journal Cell Reports.