Interactions of Bacterial Quorum Sensing Signals with Model Lipid Membranes: Influence of Membrane Composition on Membrane Remodeling

Abstract

We report the influence of membrane composition on the multiscale remodeling of multicomponent lipid bilayers initiated by contact with the amphiphilic bacterial quorum sensing signal N-(3-oxo)-dodecanoyl-l-homoserine lactone (3-oxo-C12-AHL) and its anionic headgroup hydrolysis product, 3-oxo-C12-HS. We used fluorescence microscopy and quartz crystal microbalance with dissipation (QCM-D) to characterize membrane reformation that occurs when these amphiphiles are placed in contact with supported lipid bilayers (SLBs) composed of (i) 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) containing varying amounts of cholesterol or (ii) mixtures of DOPC and either 1,2-dioleoyl-sn-glycero-3-phospho­ethanol­amine (DOPE, a conical zwitterionic lipid) or 1,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS, a model anionic lipid). In general, we observe these mixed-lipid membranes to undergo remodeling events, including the formation and subsequent collapse of long tubules and the formation of hemispherical caps, upon introduction to biologically relevant concentrations of 3-oxo-C12-AHL and 3-oxo-C12-HS in ways that differ substantially from those observed in single-component DOPC membranes. These differences in bilayer reformation and their associated dynamics can be understood in terms of the influence of membrane composition on the time scales of molecular flip-flop, lipid packing defects, and lipid phase segregation in these materials. The lipid components investigated here are representative of classes of lipids that comprise both naturally occurring cell membranes and many useful synthetic soft materials. These studies thus represent a first step toward understanding the ways in which membrane composition can impact interactions with this important class of bacterial signaling molecules.

Influence of Cuticular Waxes from Triticale on Rumen Fermentation: A Metabolomic and Microbiome Profiling Study

“…Among the metabolites significantly increased their concentrations in the wax-added groups compared to the non-wax group, sn -glycero-3-phosphoethanolamine is a molecule involved in cellular membranes and lipid metabolism, and ferulic acid is released during the breakdown of plant materials, contributing to the energy and nutrient supply for ruminant animals . Furthermore, a higher abundance of sn -glycero-3-phosphoethanolamine was also observed in the low-wax group compared with the high-wax group.…”

“…This suggested that changes in rumen microbial communities were associated with changes in rumen metabolites. Significantly differential metabolites (top 30) in the rumen between NW and LW, NW and HW, and LW and HW are shown in Figure 6A Among the metabolites significantly increased their concentrations in the wax-added groups compared to the non-wax group, sn-glycero-3-phosphoethanolamine is a molecule involved in cellular membranes and lipid metabolism, 53 and ferulic acid is released during the breakdown of plant materials, contributing to the energy and nutrient supply for ruminant animals. 54 Furthermore, a higher abundance of sn-glycero-3phosphoethanolamine was also observed in the low-wax group compared with the high-wax group.…”

Virtual Special Issue Honoring the Legacy of Dr. Bettye Washington Greene

“…Gonzalez and Groves also use DFT to define propylene glycol stereoisomers suitable for adsorption potential energies in creating renewable fuel cell sources. This section also includes Gahan et al’s studies toward understanding the role of membrane composition in bacterial quorum sensing as well as work characterizing the various biologically relevant membranes from Wood et al, Faizi et al, and Bali et al…”

“…Gonzalez and Groves 25 also use DFT to define propylene glycol stereoisomers suitable for adsorption potential energies in creating renewable fuel cell sources. This section also includes Gahan et al's 26 studies toward understanding the role of membrane composition in bacterial quorum sensing as well as work characterizing the various biologically relevant membranes from Wood et al, 35 Faizi et al, 36 and Bali et al 37 ■ IONIC LIQUIDS, LIQUID CRYSTALS, AND EMULSIONS This section of the VSI includes articles that describe a variety of different liquid colloidal solutions. Edgehouse et al 38 and Han et al 39 both describe the characterization of various ionic liquids, Darlington et al 27 report on the use of biocompatible ionic liquids to improve blood detection, and Birrer et al 28 describe ionic liquid-in-water emulsions.…”

“…Dr. Phillips’ reflection provides a unique perspective on the lasting influence and legacy of Dr. Greene. Following this personal reflection, we present invited research articles submitted to this VSI to honor Dr. Greene and further recognize the importance of her work in advancing the discipline. − We then include selected recent articles published in Langmuir that showcase advances within research areas related to those that Dr. Greene devoted her scientific career to advancing. − This collection of articles is divided into four sections that reflect the breadth of topics influenced by Dr. Greene’s accomplishments (Table ).…”