Fluorescence studies of a labeled model peptide in membrane and micellar media

Both micellar and lipid membrane systems have been used as models to provide further information regarding peptide properties in biological systems. Peptides are basic architectural units in nature and the study of their properties in membranes and other non-homogeneous media is of fundamental importance. We present the results for a time-resolved and steady state fluorescence study of two 4-methoxy-naphthalene labelled twelve amino acid residue model peptides that we have synthesised. One peptide, with a N-tert-Butoxycarbonyl (BOC) modified N-terminal, was incorporated into small unilamellar vesicles of L-(alpha) dipalmitoylphosphatidycholine (DPPC) and the other, with a free amino group, into inverse micelles of sodium bis (2-ethylhexyl) sulfosuccinate (AOT) in 2,2,4-trimethylpentane. Steady state fluorescence and time-resolved fluorescence lifetime and anisotropy measurements show the first peptide to be situated in the lipid bilayer. In the inverse micelle system there is evidence for the peptide being situated at the surfactant waterpool interface.

[1]  Y. Kirino,et al.  Effect of salts on conformational change of basic amphipathic peptides from β-structure to α-helix in the presence of phospholipid liposomes and their channel-forming ability , 1993 .

[2]  Enrico Gratton,et al.  Hydration and protein substates: Fluorescence of proteins in reverse micelles , 1990 .

[3]  P. Luisi,et al.  Proteins solubilized in organic solvents via reverse micelles: thermodynamic studies , 1990 .

[4]  G. A. Krei,et al.  Extraction of enzymes by reverse micelles , 1992 .

[5]  P. Luisi,et al.  Application of reverse micelles for the extraction of proteins. , 1986, Biochemical and biophysical research communications.

[6]  J. Knutson,et al.  Interaction of influenza hemagglutinin amino-terminal peptide with phospholipid vesicles: a fluorescence study. , 1991, Biochemistry.

[7]  M. Federwisch,et al.  Enhanced biopotency of synthetic C3a analogues by membrane binding. A fluorescence anisotropy decay study. , 1992, Biophysical chemistry.

[8]  M. Zulauf,et al.  Inverted micelles and microemulsions in the ternary system water/aerosol-OT/isooctane as studied by photon correlation spectroscopy , 1979 .

[9]  Y. Imanishi,et al.  Orientation and aggregation of hydrophobic helical peptides in phospholipid bilayer membrane. , 1993, Biochimica et Biophysica Acta.

[10]  L. Gierasch,et al.  Fluorescence analysis of tryptophan-containing variants of the LamB signal sequence upon insertion into a lipid bilayer. , 1991 .

[11]  M. Prieto,et al.  INTERACTION OF THE PEPTIDE HORMONE ADRENOCORTICOTROPIC ACTH(l‐24), WITH A MEMBRANE MODEL SYSTEM: A FLUORESCENCE STUDY * , 1993, Photochemistry and photobiology.

[12]  J M Prausnitz,et al.  Mechanisms of protein solubilization in reverse micelles , 1992, Biotechnology and bioengineering.

[13]  M. Manning,et al.  Enhanced solubility of proteins and peptides in nonpolar solvents through hydrophobic ion pairing , 1993 .