Release of content through mechano-sensitive gates in pressurized liposomes.
Mechano-sensitive channels are ubiquitous membrane proteins that activate in response to increasing tension in the lipid membrane. They facilitate a sudden, nonselective release of solutes and water that safeguards the integrity of the cell in hypo- or hyper-osmotic shock conditions. We have simulated the rapid release of content from a pressurized liposome through a particular mechano-sensitive protein channel, MscL, embedded in the liposomal membrane. We show that a single channel is able to relax the liposome, stressed to the point of bursting, in a matter of microseconds. We map the full activation-deactivation cycle of MscL in near-atomic detail and are able to quantify the rapid decrease in liposomal stress as a result of channel activation. This provides a computational tool that opens the way to contribute to the rational design of functional nano-containers.
Groningen Biomolecular Sciences and Biotechnology Institute, Department of Biophysical Chemistry, University of Groningen, Nijenborgh 4, 9747AG Groningen, The Netherlands. m.j.louhivuori@rug.nl
Martti
M
Louhivuori
H Jelger
HJ
Risselada
Erik
E
van der Giessen
Siewert J
SJ
Marrink
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D018360:Crystallography, X-Ray; D004548:Elasticity; D015640:Ion Channel Gating / Q000502:physiology*; D007473:Ion Channels / Q000737:chemistry / Q000378:metabolism; D008081:Liposomes / Q000378:metabolism*; D040542:Mechanotransduction, Cellular; D008958:Models, Molecular; D011312:Pressure; D012212:Rheology; D012997:Solvents; D013312:Stress, Physiological; D013997:Time Factors
D001426:Bacterial Proteins; D007473:Ion Channels; D008081:Liposomes; D012997:Solvents; C116377:Tb-MscL protein, Mycobacterium tuberculosis