title: Phospholipid asymmetry in the plasma membrane of malaria infected erythrocytes.
abstract: The transbilayer distribution of glycerophospholipids in the plasma membrane of Plasmodium knowlesi infected erythrocytes was studied by using lysine-116-epsilon-N-palmitoyl amidinated pancreatic phospholipase A2. As a consequence of its superior membrane penetrating capacities, this modified enzyme rapidly degrades its substrates in the outer membrane leaflet of intact erythrocytes, a property that makes the enzyme an excellent tool to study the malaria parasitized red cell. The modified phospholipase A2 caused a nonlytic hydrolysis of up to 12-15% of the phosphatidylethanolamine and none of the phosphatidylserine in the red cell membrane, irrespective of whether the cells harboured trophozoite and schizont stages of parasites or no parasites at all. The absence of phosphatidylserine at the exterior surface of Plasmodium infected erythrocytes was confirmed by applying the prothrombinase assay on Plasmodium falciparum infected human erythrocytes. Consequently, the results from these and previous studies indicate that the plasma membrane of Plasmodium infected erythrocytes exhibit a normal transbilayer phospholipid asymmetry.
authors.affiliation: Centrum voor Biomembranen en Lipide Enzymologie, Rijksuniversiteit te Utrect, Utrecht, The Netherlands.
authors.forename: G N
authors.initials: GN
authors.lastname: Moll
authors.forename: H J
authors.initials: HJ
authors.lastname: Vial
authors.forename: E M
authors.initials: EM
authors.lastname: Bevers
authors.forename: M L
authors.initials: ML
authors.lastname: Ancelin
authors.forename: B
authors.initials: B
authors.lastname: Roelofsen
authors.forename: P
authors.initials: P
authors.lastname: Comfurius
authors.forename: A J
authors.initials: AJ
authors.lastname: Slotboom
authors.forename: R F
authors.initials: RF
authors.lastname: Zwaal
authors.forename: J A
authors.initials: JA
authors.lastname: Op den Kamp
authors.forename: L L
authors.initials: LL
authors.lastname: van Deenen
mesh_terms: D000818:Animals; D004910:Erythrocyte Membrane / Q000378:metabolism*; D004912:Erythrocytes / Q000469:parasitology; D008051:Lipid Bilayers / Q000097:blood; D008252:Macaca fascicularis; D008253:Macaca mulatta; D008288:Malaria / Q000097:blood* / Q000469:parasitology; D008563:Membrane Lipids / Q000097:blood; D010718:Phosphatidylserines / Q000097:blood; D010741:Phospholipases A; D054467:Phospholipases A2; D010743:Phospholipids / Q000097:blood*
chemical_list: D008051:Lipid Bilayers; D008563:Membrane Lipids; D010718:Phosphatidylserines; D010743:Phospholipids; D010741:Phospholipases A; D054467:Phospholipases A2