Membrane protein insertion through a mitochondrial β-barrel gate

Science              online article

The biogenesis of mitochondria, chloroplasts, and Gram-negative bacteria requires the insertion of beta-barrel proteins into the outer membranes mediated by homologous Omp85 proteins. We have mapped the interaction of a precursor in transit with the mitochondrial Omp85-channel Sam50 in the native membrane environment. The precursor is translocated into the channel interior, interacts with an internal loop, and inserts into the lateral gate by beta-signal exchange.