Conformational and Associative Behaviours of the Third Helix of Antennapedia Homeodomain in Membrane‐Mimetic Environments
Open Access
- 1 December 1996
- journal article
- Published by Wiley in European Journal of Biochemistry
- Vol. 242 (2), 372-386
- https://doi.org/10.1111/j.1432-1033.1996.0372r.x
Abstract
The third helix of antennapedia homeodomain pAntp-(43–58) can translocate through cell membrane and has been used as an intracellular vehicle for delivering peptides and oligonucleotides. The conformational and associative behaviour of two peptidic vectors pAntp-(43–58) and [Pro50]pAntp-(43–58) has been analyzed by different biophysical methods. pAntp-(43–58) adopts an amphipathic helical structure in 30% (by vol.) hexafluoroisopropanol, in perfluoro-tert-butanol and in the presence of SDS micelles. CD spectra indicate that the conformation of [Pro50]pAntp-(43–58) in contrast to pAntp-(43–58) is independent of the media used. 1H-NMR spectroscopy in SDS micelles or in perfluoro-tert-butanol allows detection of aggregated peptides probably in a ribbon 27 type conformation. These conformations became the predominant structure when Gln50 was replaced by Pro50. Interproton-distance restraints derived from NOE measurements have been classified in two groups corresponding to two types of structures: α-helix and essentially extended structures. Consecutive CHα(i)/CHα(i+1) NOES are only compatible with aggregates. Simulated annealing calculation of dimeric structure agrees with φ and ψ angles in the β-sheet and γ-turn regions. Fluorescence spectroscopy analysis has shown that the indole groups of both peptides penetrate into SDS micelles; both peptides also induce the formation of micelles at very low concentration of SDS (20 μM). Similar interaction was observed with reverse-phase micelles made of bis(2-ethyhexyl) sodium sulfosuccinate and small unilamellar vesicles (SUV) made of a mixture of phosphatidylcholine/phosphatidylserine. 31P-NMR of vesicles (SUV and large unilamellar vesicles) indicated that the addition of pAntp analogues did not affect the size of phosphatidylcholine/phosphatidylserine vesicles. The addition of pAntp analogues to lipidic dispersions modulates lipid polymorphism in different ways depending on the mixtures of acidic lipids.Keywords
This publication has 60 references indexed in Scilit:
- Native Escherichia coli OmpF Porin Surfaces Probed by Atomic Force MicroscopyScience, 1995
- Relationship between nuclear magnetic resonance chemical shift and protein secondary structureJournal of Molecular Biology, 1991
- Gradient-enhanced proton-detected heteronuclear multiple-quantum coherence spectroscopyJournal of Magnetic Resonance (1969), 1991
- The Photosynthetic Reaction Center from the Purple Bacterium Rhodopseudomonas viridisScience, 1989
- Interactions between membranes and cytolytic peptidesBiochimica et Biophysica Acta (BBA) - Reviews on Biomembranes, 1986
- Thermodynamic, motional, and structural aspects of the gramicidin-induced hexagonal HII phase formation in phosphatidylethanolamineBiochemistry, 1985
- MLEV-17-based two-dimensional homonuclear magnetization transfer spectroscopyJournal of Magnetic Resonance (1969), 1985
- Structural changes in membranes produced by the binding of small amphipathic moleculesBiochemistry, 1984
- Application of phase sensitive two-dimensional correlated spectroscopy (COSY) for measurements of 1H-1H spin-spin coupling constants in proteinsBiochemical and Biophysical Research Communications, 1983
- 1H‐nmr parameters of the common amino acid residues measured in aqueous solutions of the linear tetrapeptides H‐Gly‐Gly‐X‐L‐Ala‐OHBiopolymers, 1979