title: Reconstitution of surfactant activity by using the 6 kDa apoprotein associated with pulmonary surfactant.
abstract: Lipid extracts of bovine pulmonary surfactant containing the 6 kDa apoprotein, but lacking the 35 kDa apoprotein, can mimic the essential characteristics of pulmonary surfactant on a pulsating-bubble surfactometer. Reconstituted surfactant can be produced by combining silicic acid fractions containing 6 kDa apoprotein and phosphatidylglycerol with phosphatidylcholine. Treatment of the protein-containing fraction with proteolytic enzymes abolishes its efficacy. These results indicate that the presence of the 6 kDa apoprotein can account for some of the essential physical and biological characteristics of pulmonary surfactant. Immunodiffusion studies indicate that, contrary to earlier suggestions, the 6 kDa apoprotein is not structurally related to the major surfactant apoprotein that has a molecular mass of 35 kDa.
mesh_terms: D000818:Animals; D001059:Apoproteins / Q000378:metabolism*; D002417:Cattle; D002853:Chromatography, Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005779:Immunodiffusion; D010743:Phospholipids; D011402:Pronase; D011663:Pulmonary Surfactants / Q000378:metabolism*; D013500:Surface Tension; D014357:Trypsin
chemical_list: D001059:Apoproteins; D010743:Phospholipids; D011663:Pulmonary Surfactants; D014357:Trypsin; D011402:Pronase