title: Bacterial proteins with N-terminal leader sequences resembling mitochondrial targeting sequences of eukaryotes.
abstract: Amphipathic, alpha-helical, leader sequences, analogous to those that direct nuclear-encoded eukaryotic proteins into mitochondria, have been found in one and only one class of bacterial integral membrane proteins. These bacterial proteins are the sugar permeases of the phosphoenolpyruvate-dependent phosphotransferase system. The amphipathic leader sequence in each of these proteins is terminated by a helix breaker, either a prolyl residue or 2 adjacent glycyl residues. Preliminary evidence suggests that these leader sequences function to target the proteins to the envelope fraction of the prokaryotic cell during their biosynthesis.
authors.affiliation: Department of Biology, University of California San Diego, La Jolla 92093.
authors.forename: M H
authors.initials: MH
authors.lastname: Saier
authors.forename: M
authors.initials: M
authors.lastname: Yamada
authors.forename: K
authors.initials: K
authors.lastname: Suda
authors.forename: B
authors.initials: B
authors.lastname: Erni
authors.forename: B
authors.initials: B
authors.lastname: Rak
authors.forename: J
authors.initials: J
authors.lastname: Lengeler
authors.forename: G C
authors.initials: GC
authors.lastname: Stewart
authors.forename: E B
authors.initials: EB
authors.lastname: Waygood
authors.forename: G
authors.initials: G
authors.lastname: Rapoport
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000032:analysis*; D008565:Membrane Proteins / Q000032:analysis*; D008928:Mitochondria / Q000032:analysis; D008969:Molecular Sequence Data; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000032:analysis*; D011487:Protein Conformation; D021382:Protein Sorting Signals / Q000032:analysis*
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D021382:Protein Sorting Signals; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System