Researchers at the University of Freiburg have succeeded in describing how so-called beta-barrel proteins are inserted into the membranes of mitochondria. The proteins enable mitochondria to import and export molecules. With this discovery, the team led by Prof. Dr. Nils Wiedemann and Prof. Dr. Nikolaus Pfanner, in cooperation with the group of Prof. Dr. Carola Hunte, has clarified a fundamental question of protein biochemistry. The findings are published in the journal Science.