Lipid corralling and poloxamer squeeze-out in membranes.
Using x-ray scattering measurements we have quantitatively determined the effect of poloxamer 188 (P188), a polymer known to seal damaged membranes, on the structure of lipid monolayers. P188 selectively inserts into low lipid-density regions of the membrane and "corrals" lipid molecules to pack tightly, leading to unexpected Bragg peaks at low nominal lipid density and inducing lipid/poloxamer phase separation. At tighter lipid packing, the once inserted P188 is squeezed out, allowing the poloxamer to gracefully exit when the membrane integrity is restored.
Wu
Guohui
G
Department of Chemistry, Institute for Biophysical Dynamics & James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
Majewski
Jaroslaw
J
Ege
Canay
C
Kjaer
Kristian
K
Weygand
Markus Jan
MJ
Lee
Ka Yee C
KY
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D000388:Air; D000818:Animals; D006801:Humans; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry*; D020442:Poloxamer / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D013696:Temperature; D014867:Water
D008051:Lipid Bilayers; D008055:Lipids; D011108:Polymers; D014867:Water; D020442:Poloxamer; D015060:1,2-Dipalmitoylphosphatidylcholine