Transmembrane β-peptide helices as molecular rulers at the membrane surface

Area of Science:

• Biophysical Chemistry
• Materials Science
• Molecular Biology

Background:

• Beta-peptides form rigid 14-helices with regular side-chain positioning, suitable for molecular ruler backbones.
• These structures can be functionalized with probes and anchored in biological environments like lipid membranes.

Purpose of the Study:

• To utilize beta-peptide helices as molecular rulers anchored within lipid bilayer membranes.
• To determine the distances of molecular probes attached to the beta-peptide ruler from the membrane surface.

Main Methods:

• Anchoring beta-peptide helices into lipid bilayer membranes.
• Utilizing graphene-induced energy transfer (GIET) spectroscopy to measure distances.
• Functionalizing the beta-peptide with fluorophores at specific sites.

Main Results:

• Successfully anchored and elongated beta-peptide helices within the membrane environment.
• Accurately determined distances between covalently bound probes and the membrane surface using GIET.
• Validated the beta-peptide molecular ruler concept for distance measurements in membranes.

Conclusions:

• Beta-peptide helices are effective molecular rulers for probing distances in lipid membranes.
• GIET spectroscopy provides a precise method for measuring distances with membrane-anchored molecular rulers.
• This approach has potential applications in understanding membrane-associated biological processes.