title: Effects of fibrinogens on phase transitions in lipid model membrane systems.
abstract: An abnormal fibrinogen that caused aggregation of red blood cells (RBC) in a patient with gangrene was examined by real-time X-ray diffraction to determine its effects on dipalmitoylphosphatidylcholine (DPPC) and 1-palmitoyl-2-oleoylphosphatidylethanolamine (POPE) phase transitions. Similar studies were done with normal fibrinogen and results were compared. Both types of fibrinogen slightly increased the L alpha-->HII phase transition temperature and the HII phase parameters for POPE, while neither fibrinogen significantly affected the order-disordered acyl chain transitions in the lipid bilayer phase. However, fibrinogen differentially influenced the bilayer unit cell parameter of the gel and disordered bilayer and the gel state ripple phase. These results can be interpreted as indicating that fibrinogen has little effect on the balance of gel and disordered acyl chains in the lipid bilayer, but may influence membrane functions dependent on non-bilayer phases.
authors.affiliation: Department of Physics, Bucknell University, Lewisburg, Pennsylvania 17837.
authors.forename: B A
authors.initials: BA
authors.lastname: Cunningham
authors.forename: O
authors.initials: O
authors.lastname: Küçük
authors.forename: H C
authors.initials: HC
authors.lastname: Kwaan
authors.forename: M P
authors.initials: MP
authors.lastname: Westerman
authors.forename: D
authors.initials: D
authors.lastname: Tracy
authors.forename: L J
authors.initials: LJ
authors.lastname: Lis
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D004903:Erythrocyte Aggregation; D005340:Fibrinogen / Q000737:chemistry / Q000494:pharmacology*; D006358:Hot Temperature; D006801:Humans; D008051:Lipid Bilayers; D010714:Phosphatidylethanolamines / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D008051:Lipid Bilayers; D010714:Phosphatidylethanolamines; C057561:1-palmitoyl-2-oleoylphosphatidylethanolamine; D015060:1,2-Dipalmitoylphosphatidylcholine; D005340:Fibrinogen