Lipid saturation and head group composition have a pronounced influence on the membrane insertion equilibrium of amphipathic helical polypeptides

The intricate link between membrane lipid structure and composition and membrane structural properties in bacterial membranes

“…The perturbation of a membrane upon exposure to AMPs can cause changes in different physical properties of membranes, including thickening/thinning, membrane expansion, specic domain formation and redistribution, membrane curvature deformation, and non-lamellar phases and lateral phase segregation, which can all lead to destabilizing the membrane, increased permeability, and loss of membrane potential. [174][175][176] The selective antibacterial activity of AMPs is strongly inuenced by the lipid compositions of bacterial membranes where the negatively charged phospholipids play a prominent role in promoting peptide binding and insertion into the membrane, while other peptides tend to bind primarily at the interfacial region of membrane consisting solely of zwitterionic lipids. Following exposure to AMPs, the phenotypic changes in membranes associated with alterations in lipid composition and structure, and subsequently impacting on the physical properties of the membrane, are emerging as potential mechanisms to counteract the action of AMPs.…”

“…The perturbation of a membrane upon exposure to AMPs can cause changes in different physical properties of membranes, including thickening/thinning, membrane expansion, specific domain formation and redistribution, membrane curvature deformation, and non-lamellar phases and lateral phase segregation, which can all lead to destabilizing the membrane, increased permeability, and loss of membrane potential. 174–176…”

LL-37: Structures, Antimicrobial Activity, and Influence on Amyloid-Related Diseases

“…Solid-state NMR is a technique used to determine the structure and dynamics of a variety of solids and semi-solids (examples include liquid crystalline systems), and it is an ideal approach to investigate biological membranes that are difficult to study with other biophysical techniques like solution NMR or crystallization techniques [ 226 , 227 , 228 , 229 , 230 ]. In the case of LL-37, solid-state NMR experiments were used to determine the backbone conformation, dynamics, and membrane orientation in order to determine the mechanism of lipid membrane disruption by LL-37.…”

Rhomboid-catalyzed intramembrane proteolysis requires hydrophobic matching with the surrounding lipid bilayer

“…A mismatch between the hydrophobic thickness of the protein and the surrounding membrane results in unfavorable free energy that can be relieved by several mechanisms ( 14 , 16 ): (i) The surrounding lipids can adjust their chain order to increase or decrease acyl chain length to match the thickness of the protein, (ii) the protein can tilt or adjust its α-helical content to respond to the thickness difference of the surrounding membrane, and/or (iii) proteins can cluster to minimize the interaction with a mismatched lipid bilayer. Furthermore, membrane charge and the degree of lipid chain unsaturation influence protein-lipid interactions ( 17 ). For GlpG, molecular dynamics (MD) simulations have suggested that the rhomboid fold thins lipid double layers of varying composition by up to 4 Å ( 10 ).…”