The Interfacial Interactions of Glycine and Short Glycine Peptides in Model Membrane Systems.

Kaitlin A Doucette,Prangthong Chaiyasit,Cameron Van Cleave,Anan Tongraar,Callan A Knebel,Kayli N Martinez,Donn L Calkins,Debbie C Crans

doi:10.3390/ijms22010162

Abstract

The interactions of amino acids and peptides at model membrane interfaces have considerable implications for biological functions, with the ability to act as chemical messengers, hormones, neurotransmitters, and even as antibiotics and anticancer agents. In this study, glycine and the short glycine peptides diglycine, triglycine, and tetraglycine are studied with regards to their interactions at the model membrane interface of Aerosol-OT (AOT) reverse micelles via 1H NMR spectroscopy, dynamic light scattering (DLS), and Langmuir trough measurements. It was found that with the exception of monomeric glycine, the peptides prefer to associate between the interface and bulk water pool of the reverse micelle. Monomeric glycine, however, resides with the N-terminus in the ordered interstitial water (stern layer) and the C-terminus located in the bulk water pool of the reverse micelle.

Highlights

IntroductionPeptides play an important role as antibiotics, such as bacitracin and colistin, as well as antimicrobial peptides (AMPs, referred to as host defense peptides) [4,5,6]
The chemical shifts of G, GG, GGG, and GGGG were examined by 1 H NMR spectroscopy to compare their chemical shifts in aqueous solution with those peaks obtained in the environment of the reverse micelles (RMs) model membrane (Sections 2.1–2.4)
Studies exploring the interaction of G, GG, GGG, and GGGG compounds with model membrane interfaces measured in microemulsions (AOT RMs) using 1 H NMR spectroscopy and dynamic light scattering (DLS) indicate that G peptides prefer to locate themselves at the edge of the charged reverse micellar interface, between the water pool and interface at the stern layer

Summary

Introduction

Peptides play an important role as antibiotics, such as bacitracin and colistin, as well as antimicrobial peptides (AMPs, referred to as host defense peptides) [4,5,6]

Methods

Results

Discussion

Conclusion