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.
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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 timescales. 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 scales and timescales. 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 timescales. Our results suggest that bilayer-based cavitation is what generally limits the magnitude of negative pressures in liquids that contain lipid bilayers.
more » « less- NSF-PAR ID:
- 10147720
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 20
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 10733-10739
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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