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bioRxiv · 10.1101/2020.06.05.133868

The Mechanism of Vesicle Solubilization by the Detergent Sodium Dodecyl Sulfate

Juan-Colas, J.·Dresser, L.·Morris, K.·Lagadou, H.·Ward, R. H.·Burns, A.·Tear, S.·Johnson, S.·Leake, M. C.·Quinn, S. D.
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Abstract

Membrane solubilization by sodium dodecyl sulfate (SDS) is indispensable for many established biotech-nological applications, including viral inactivation and protein extraction. Although the ensemble thermo-dynamics have been thoroughly explored, the underlying molecular dynamics have remained inaccessible, owing to major limitations of traditional measurement tools. Here, we integrate multiple advanced biophysical approaches to gain multi-angle insight into the time-dependence and fundamental kinetic steps associated with the solubilization of single sub-micron sized vesicles in response to SDS. We find that the accumulation of SDS molecules on in-tact vesicles triggers biphasic solubilization kinetics comprising an initial vesicle expansion event followed by rapid lipid loss and micellization. Our findings support a general mechanism of detergent-induced membrane solubilization and we expect the framework of correlative biophysical technologies presented here will form a general platform for elucidating the complex kinetics of membrane perturbation induced by a wide variety of surfactants and disrupting agents.

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Juan-Colas, J., Dresser, L., Morris, K., Lagadou, H., Ward, R. H., Burns, A., Tear, S., Johnson, S., Leake, M. C., Quinn, S. D.. 2020-06-06. The Mechanism of Vesicle Solubilization by the Detergent Sodium Dodecyl Sulfate. https://doi.org/10.1101/2020.06.05.133868

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