Thermally driven fission of protocells

Romain Attal

doi:10.1016/j.bpj.2021.08.020

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arXiv · 2101.09096

Thermally driven fission of protocells

Romain Attal

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Abstract

We propose a simple mechanism for the self-replication of protocells. Our main hypothesis is that the amphiphilic molecules composing the membrane bilayer are synthesised inside the protocell through globally exothermic chemical reactions. The slow increase of the inner temperature forces the hottest molecules to move from the inner leaflet to the outer leaflet of the bilayer. This asymmetric translocation process makes the outer leaflet grow faster than the inner leaflet. This differential growth increases the mean curvature and amplifies any local shrinking of the protocell until it splits in two.

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Romain Attal. 2021-01-22. Thermally driven fission of protocells. https://doi.org/10.1016/j.bpj.2021.08.020

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