Membrane insertion and lateral mobility of synthetic amphiphilic signal peptides in lipid model membranes.
Amphiphilic signal sequences with the potential to form alpha-helices with a polar, charged face and an apolar face are common in proteins which are imported into mitochondria, in the PTS permeases of bacteria, and in bacterial rhodopsins. Synthetic peptides of such sequences partition into the surface region of lipid membranes where they can adopt different secondary structures. A finely controlled balance of electrostatic and hydrophobic interactions determines the 'affinity' of amphiphilic signal peptides for lipid membranes, as well as the structure, orientation and depth of penetration of these peptides in lipid bilayer membranes. The ability of an individual peptide to associate with lipid bilayer membranes in several different modes is, most likely, a general feature of amphiphilic signal peptides and is reflected in several common physical properties of their amino acid sequences.
Tamm
L K
LK
Department of Physiology, University of Virginia, Health Sciences Center, Charlottesville 22908.
D000595:Amino Acid Sequence; D007425:Intracellular Membranes / Q000378:metabolism*; D008051:Lipid Bilayers / Q000378:metabolism*; D008560:Membrane Fluidity / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology; D026901:Membrane Transport Proteins / Q000378:metabolism; D008566:Membranes / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D008969:Molecular Sequence Data; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000378:metabolism; D011487:Protein Conformation; D021382:Protein Sorting Signals / Q000378:metabolism*; D012243:Rhodopsin / Q000378:metabolism
D008051:Lipid Bilayers; D026901:Membrane Transport Proteins; D021382:Protein Sorting Signals; D012243:Rhodopsin; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System