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.
Department of Chemistry, Institute for Biophysical Dynamics & James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
Guohui
G
Wu
Jaroslaw
J
Majewski
Canay
C
Ege
Kristian
K
Kjaer
Markus Jan
MJ
Weygand
Ka Yee C
KY
Lee
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