Micellar Composition Affects Lipid Accretion Kinetics in Molecular Dynamics Simulations

Mixed lipid micelles were proposed to facilitate the emergence of life through their documented growth dynamics and catalytic properties. Our research predicted that micellar self-reproduction is possible through composition-driven catalyzed accretion of lipid molecules in heterogeneous systems, reaching states that allow micellar growth and split while maintaining compositional homeostasis. However, experimentally studying catalyzed accretion in mixed micelles is technically challenging. Here, we employ atomistic Molecular Dynamics simulations to examine the self-assembly of variegated lipid assemblies allowing us to derive entry and exit rates of monomeric lipids into pre-micelles with different compositions. We observe considerable selective rate-modifications that are compositionally-driven, and illustrate their underlying mechanisms as well as the energy contributions that facilitate these kinetic effects. Lastly, we describe the measured potential for compositional homeostasis in our simulated mixed micelles, the basis for micellar self-reproduction, with implications for the study of the origin of life.