Degree Name
MS (Master of Science)
Program
Chemistry
Date of Award
12-2025
Committee Chair or Co-Chairs
Robert Frank Standaert
Committee Members
Jeremy Christopher Smith, Dane William Scott, Micholas Dean Smith.
Abstract
Membrane integrity under chemical stress is critical to cellular survival and industrial microbial bioproduction, yet the molecular basis of bilayer resilience remains poorly understood. Using all-atom molecular dynamics simulation, we compare the effect of increasing concentrations of 1‑butanol on membranes composed of straight-chain (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC) and branched-chain (1-anteiso-palmitoyl-2-palmitoyl-sn-glycero-3-phosphocholine, APPC) lipids, which differ in the point of attachment of a single methyl group. In the absence of butanol, both membranes exhibit well-ordered architectures consistent with experimental benchmarks; however, under increasing solvent stress, their behaviors diverge markedly. DPPC membranes display gradual thinning, modest area per lipid (APL) expansion, and sustained acyl chain order, resulting in only moderate mechanical weakening. In contrast, APPC bilayers thin rapidly, expand laterally, and lose chain order, resulting in significant interleaflet overlap and a sharp decline in bending modulus. Our findings underscore how subtle differences in lipid tail architecture can dramatically influence membrane vulnerability to organic solvents.
Document Type
Thesis - unrestricted
Recommended Citation
Aggrey, Joshua Olaf, "Divergent Responses of Branched-Chain and Straight-Chain Lipid Membranes to Butanol Stress Revealed by All-Atom Molecular Dynamics Simulations" (2025). Electronic Theses and Dissertations. Paper 4596. https://dc.etsu.edu/etd/4596
Copyright
Copyright by the authors.
