Barreling through the outer membrane

The protein translocation channel of the outer mitochondrial membrane is th ought to be a rigid P-barrel, Newly synthesized membrane proteins apparentl y do not escape laterally from this channel into the lipid bilayer, but mus t insert into the outer membrane from the aqueous phase. A study on the bio genesis of the mitochondrial outer membrane translocation machinery now sho ws that the subunit forming the protein import channel is first translocate d across the outer membrane and then reinserted.