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Title: Cavitation in lipid bilayers poses strict negative pressure stability limit in biological liquids
Biological and technological processes that involve liquids under negative pressure are vulnerable to the formation of cavities. Maximal negative pressures found in plants are around −100 bar, even though cavitation in pure bulk water only occurs at much more negative pressures on the relevant time scales. Here, we investigate the influence of small solutes and lipid bilayers, both constituents of all biological liquids, on the formation of cavities under negative pressures. By combining molecular dynamics simulations with kinetic modeling, we quantify cavitation rates on biologically relevant length and time scales. We find that lipid bilayers, in contrast to small solutes, increase the rate of cavitation, which remains unproblematically low at the pressures found in most plants. Only when the negative pressures approach −100 bar does cavitation occur on biologically relevant time scales. Our results suggest that bilayerbased cavitation is what generally limits the magnitude of negative pressures in liquids that contain lipid bilayers.
Authors:
; ; ; ; ;
Award ID(s):
1754850
Publication Date:
NSF-PAR ID:
10142224
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
ISSN:
1091-6490
Sponsoring Org:
National Science Foundation
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