Peptide Folding Dynamics: A Time-Resolved Study from the Nanosecond to the Microsecond Time Regime
- 25 October 2006
- journal article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry B
- Vol. 110 (45), 22834-22841
- https://doi.org/10.1021/jp063078w
Abstract
Time-resolved spectroscopies, spanning from the nanosecond to the microsecond time regime, coupled with molecular mechanics calculations, allowed us to assess the most populated conformations in solution of a series of analogues of trichogin GA IV, a natural undecapeptide showing significant antimicrobial activity. This peptide is characterized by a high content of the conformationally constrained α-aminoisobutyric acid and by a glycine−glycine motif in the central part of the sequence. Nanosecond time-resolved fluorescence experiments were performed to determine the conformational properties of the peptide analogues in solution, while transient absorption measurements allowed us to study the peptide dynamics on the microsecond time scale. Because the peptides examined were functionalized by a fluorescent probe at the N-terminus and a nitroxide quencher placed along the backbone at three different positions, the distance-dependent fluorophore−quencher interaction was exploited to obtain a deeper insight into their three-dimensional structural and dynamical properties. Further information on the conformational and dynamical features was obtained by photophysical experiments as a function of the viscosity and polarity of the medium. Taken together, the results revealed a transition from an elongated, helical conformation to a family of compact, folded structures mimicking a helix−turn−helix motif, which may represent a model of the early steps of the protein hydrophobic collapse.Keywords
This publication has 23 references indexed in Scilit:
- Dynamics of Formation of a Helix–Turn–Helix Structure in a Membrane‐Active Peptide: A Time‐Resolved Spectroscopic StudyChemBioChem, 2006
- A topographically and conformationally constrained, spin‐labeled, α‐amino acid: crystallographic characterization in peptides*Chemical Biology & Drug Design, 2005
- Protein Kinase D-Mediated Anterograde Membrane Trafficking Is Required for Fibroblast MotilityCurrent Biology, 2004
- Effects of Helical Distortions on the Optical Properties of Amide NH Infrared Absorption in Short Peptides in SolutionThe Journal of Physical Chemistry B, 2002
- Orientation and immersion depth of a helical lipopeptaibol in membranes using TOAC as an ESR probePeptide Science, 1999
- A Nitroxide Derivative as a Probe for Conformational Studies of Short Linear Peptides in Solution. Spectroscopic and Molecular Mechanics InvestigationThe Journal of Physical Chemistry B, 1998
- Conformational Statistics and Energetics Analysis of Sequential Peptides Undergoing Intramolecular Transfer of Excitation EnergyThe Journal of Physical Chemistry, 1996
- Expounding endocrinologyTrends in Biochemical Sciences, 1991
- Reference materials for fluorescence measurementPure and Applied Chemistry, 1988
- Camoquin Relatives1Journal of the American Chemical Society, 1952