title: The Pandinus imperator haemolymph lipoprotein, an unusual phosphatidylserine carrying lipoprotein.
abstract: The haemolymph lipoprotein of the scorpion, Pandinus imperator was isolated and characterised. Contrary to the lipoproteins of insects and the discoidal HDL-lipoproteins of a crayfish and polychaete, the Pandinus lipoprotein consists of three instead of two apoproteins (apoPiLp I = 230 kDa, apoPiLp II = 130 kDa and apoPiLp III = 120 kDa). The apolipoproteins are arranged in varying stoichiometries as judged by cross-linking experiments. In lipoprotein samples from individual animals, the two smaller subunits occurred in a 1:1 stoichiometry, while the relative amount of the 230 kDa peptide varied. The lipoprotein is a slightly heart-shaped HDL with a diameter of approximately 15 nm. It is present in two densities of 1100 and 1190 kg/m(3), of which the latter is by far more abundant. The native molecular mass was estimated to be approximately 500 kDa. The lipid content was determined as 33.5% and consists of approximately 70% neutral lipids and approximately 30% phospholipids. Strikingly, 42.5% of the phospholipids is phosphatidylserine while phosphatidylcholine and phosphatidylethanolamine account for 55.1% and approximately 2.3%, respectively. Carbohydrate analysis suggests the presence of only high-mannose-type N-glycans. N-glycan profiling shows glycans corresponding to a size of 8.0-11.5 hexose units.
authors.affiliation: Institut für Zoologie, Johannes Gutenberg-Universität Mainz, Johannes von Müller-Weg 6, Mainz, Germany. schenks@uni-mainz.de
authors.forename: Sven
authors.initials: S
authors.lastname: Schenk
authors.forename: Heike
authors.initials: H
authors.lastname: Gras
authors.forename: Diana
authors.initials: D
authors.lastname: Marksteiner
authors.forename: Lea
authors.initials: L
authors.lastname: Patasic
authors.forename: Barbara
authors.initials: B
authors.lastname: Prommnitz
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hoeger
mesh_terms: D000818:Animals; D001692:Biological Transport; D006458:Hemolymph / Q000737:chemistry / Q000378:metabolism*; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008074:Lipoproteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D010718:Phosphatidylserines / Q000378:metabolism*; D012605:Scorpions / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D019476:Insect Proteins; D008074:Lipoproteins; D010718:Phosphatidylserines