Evolutionary conservation of biogenesis of β-barrel membrane proteins

The outer membranes of mitochondria and chloroplasts are distinguished by the presence of β-barrel membrane proteins1,2. The outer membrane of Gram-negative bacteria also harbours β-barrel proteins3. In mitochondria these proteins fulfil a variety of functions such as transport of small molecules (porin/VDAC), translocation of proteins (Tom40) and regulation of mitochondrial morphology (Mdm10)4,5,6,7. These proteins are encoded by the nucleus,...