title: [Characteristics of immobilization and catalytic properties of the Soviet commercial preparation of L-asparaginase in liposomes composed of soybean phospholipids].
abstract: The commercial preparation of 1-asparaginase was incorporated into liposomes formed from soybean phospholipids (asolectin). The inside phase volume of liposomes did not exceed 1% as calculated using fluorescence dye calcein but the efficiency of the enzyme incorporation into liposomes reached approximately 60%. The enzyme was adsorbed on outside surface due to electrostatic and hydrophobic interactions. The Km value of immobilized 1-asparaginase (2.7 X 10(-5)M) did not exceed considerably the Km values of free enzyme (1.8 X 10(-5)M) when l-asparagine was used as a substrate. The incorporation of 1-asparaginase into asolectin liposomes led to considerable increase in the enzyme thermostability at 70 degrees and also to an increase in its sensitivity to proteases and, particularly, to trypsin. The half-life periods of free and immobilized enzymes were practically similar in buffer solutions. However, the half-life period of immobilized l-asparaginase in blood serum was more than 6-fold higher as compared with that of the free enzyme.
mesh_terms: D000818:Animals; D001215:Asparaginase / Q000378:metabolism* / Q000494:pharmacology; D002384:Catalysis; D003956:Dialysis; D004800:Enzymes, Immobilized / Q000378:metabolism* / Q000494:pharmacology; D066298:In Vitro Techniques; D008081:Liposomes; D010743:Phospholipids; D051381:Rats; D013010:Sonication; D013025:Glycine max
chemical_list: D004800:Enzymes, Immobilized; D008081:Liposomes; D010743:Phospholipids; D001215:Asparaginase
vernacular_title: Issledovanie osobennosteĭ immobilizatsii i kataliticheskikh svoĭstv otechestvennogo kommercheskogo preparata L-asparaginazy v liposomakh, sformirovannykh iz fosfolipidov soevykh bobov.