Molecular Recognition of Biotinyl Hydrophobic Helical Peptides with Streptavidin at the Air/Water Interface

1994

Monolayer Properties of Hydrophobic .alpha.-Helical Peptides Having Various End Groups at the Air/Water Interface

1994

Bilayer Formation of Streptavidin Bridged by Bis(biotinyl) Peptide at the Air/Water Interface

1994

Two-Dimensional Assembly Formation of Hydrophobic Helical Peptides at the Air/Water Interface: Fluorescence Microscopic Study

1995

Monolayer formation of hydrophobic α-helical peptides, X-(Ala-Aib) 8 -Y (X=Boc-, HOOCCH 2 CH 2 CO-, biotinyl, biotinyl-(Sar) 3 -; Y=OMe, OBzl, OH), at the air/water interface was studied by the fluorescence microscopic method. Some peptides showed a mound in the π-A isotherm. When the monolayer containing a small amount of FITC-labeled peptide was held at the surface pressure corresponding to the top of the mound, bright and dark domains were observed by fluorescence microscopy. Domain formation was also observed by the addition of a cationic dye (DiIC 1 ) into the subphase underneath the peptide monolayer. The mound in the π-A isotherm is, therefore, ascribed to the phase transition from a…

Molecular recognition in biotin-streptavidin systems and analogues at the air-water interface

1992

Abstract Specific interaction between biotin and the protein streptavidin in monolayers of synthetic lipids with biotin headgroups has been shown to lead to formation of highly ordered two-dimensional streptavidin crystals. The same behaviour is observed when using desthiobiotin as lipid headgroup which exhibits a significantly lower binding constant compared with biotin (5 × 10 13 M -1 compared with 10 15 M -1 ). This offers the possibility of detaching competetively the 2D crystalline streptavidin layer by addition of free biotin to the aqueous phase. Use of lipoic acid as lipid headgroup ( K a = 7 × 10 7 M −1 ) leads to formation of small snisotropic protein domains indicating a crystall…

Supramolecular assembly using helical peptides

1997

Abstract We investigated supramolecular assemblies of various hydrophobic helical peptides. The assemblies were formed at the air/water interface or in aqueous medium. The hexadecapeptide, Boc-(Ala-Aib)8-OMe (BA16M), was reported to take α-helical structure by X-ray analysis. Several derivatives were prepared, which have the repeating sequence of Ala-Aib, Lys(Z)-Aib or Leu-Aib, or have the terminal chemically modified. CD spectra of the peptides indicated helical conformation in ethanol solution. The surface pressure-area isotherms of the peptide monolayers showed an inflection at the surface area corresponding to the cross section along the helix axis, and the monolayers were collapsed by …