title: Liposome fusion rates depend upon the conformation of polycation catalysts.
abstract: Cryo-TEM and NaCl-leakage experiments demonstrated that the cationic polymer polylysine induces fusion of anionic liposomes but that the cationic polymer poly(N-ethyl-4-vinylpyridinium bromide) (PEVP) does not, although both polymers bind strongly to the liposomes. The difference was traced to the thickness of the coatings at constant charge coverage. Polylysine is believed to form planar β-sheets that are sufficiently thin to allow membrane fusion. In contrast, looping and disorganization among adsorbed PEVP molecules physically prevent fusion. A similar effect is likely to be applicable to important polycation-induced fusion of cell membranes.
authors.affiliation: Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory, Moscow 119992, Russian Federation.
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Yaroslavov
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Sybachin
authors.forename: Ellina
authors.initials: E
authors.lastname: Kesselman
authors.forename: Judith
authors.initials: J
authors.lastname: Schmidt
authors.forename: Yeshayahu
authors.initials: Y
authors.lastname: Talmon
authors.forename: Syed A A
authors.initials: SA
authors.lastname: Rizvi
authors.forename: Fredric M
authors.initials: FM
authors.lastname: Menger
mesh_terms: D008081:Liposomes / Q000378:metabolism* / Q000648:ultrastructure; D008968:Molecular Conformation; D011073:Polyamines / Q000737:chemistry / Q000378:metabolism*; D000071228:Polyelectrolytes; D011107:Polylysine / Q000737:chemistry / Q000378:metabolism*; D011145:Polyvinyls / Q000737:chemistry / Q000378:metabolism*
chemical_list: D008081:Liposomes; D011073:Polyamines; D000071228:Polyelectrolytes; D011107:Polylysine; D011145:Polyvinyls; C027968:poly-4-vinyl-N-ethylpyridine