Activation thermodynamics of poly(ethylene glycol)-mediated model membrane fusion support mechanistic models of stalk and pore formation.

ABSTRACT: Membrane fusion, essential to eukaryotic life, is broadly envisioned as a three-step process proceeding from contacting bilayers through two semistable, nonlamellar lipidic intermediate states to a fusion pore. Here, we introduced a new, to our knowledge, experimental approach to gain insight into the nature of the transition states between initial, intermediate, and final states. Recorded time courses of lipid-mixing, content-mixing, and content-leakage associated with fusion of 23 nm vesicles in the presence of poly(ethylene glycol) at multiple temperatures were fitted globally to a three-step sequential model to yield rate constants and thereby activation thermodynamics for each step of the process, as well as probabilities of occurrence of lipid-mixing, content-mixing, or content-leaka

SUBMITTER: Chakraborty H 

PROVIDER: S-EPMC3379029 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature