Inserting membrane proteins: The YidC/Oxa1/Alb3 machinery in bacteria, mitochondria, and chloroplasts

►The YidC insertase promotes membrane insertion of a subset of proteins into the cytoplasmic membrane in bacteria. ►The YidC insertase can function as a chaperone and can facilitate the folding of membrane proteins. ►Oxa1 plays a crucial role in the assembly of the mitochodrial inner membrane proteins cytochrome c oxidase and F1Fo ATP synthase. ►Alb3 mediates the integration of SRP-dependent light-harvesting chlorophyll a, b binding proteins into the chloroplast thylakoid membrane.