Bacterial proteins with N-terminal leader sequences resembling mitochondrial targeting sequences of eukaryotes.
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.
Saier
M H
MH
Department of Biology, University of California San Diego, La Jolla 92093.
Yamada
M
M
Suda
K
K
Erni
B
B
Rak
B
B
Lengeler
J
J
Stewart
G C
GC
Waygood
E B
EB
Rapoport
G
G
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*
D001426:Bacterial Proteins; D008565:Membrane Proteins; D021382:Protein Sorting Signals; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System