title: Oxidized low-density lipoprotein-binding specificity of Asp-hemolysin from Aspergillus fumigatus.
abstract: Oxidized low-density lipoprotein (Ox-LDL) is known to be involved in the generation and progression of atherosclerosis. Ox-LDL has a number of potentially atherogenic effects on vascular cells, including the uncontrolled uptake by scavenger receptors. We have previously shown that Asp-hemolysin binds to Ox-LDL in a concentration-dependent manner. The present study was undertaken to clarify the binding specificity of Asp-hemolysin to Ox-LDL. We examined the binding specificity of Asp-hemolysin to Ox-LDL using several modified lipoproteins and scavenger receptor ligands. Asp-hemolysin bound to Ox-LDL with shorter LDL oxidation times. However, Asp-hemolysin did not bind to the acetylated LDL. The native high-density lipoprotein (n-HDL) and modified HDL (e.g., acetylated HDL, oxidized HDL) also had no Asp-hemolysin binding. Furthermore, inhibitors of the scavenger receptor binding, including maleylated BSA, polyinosinic acid, dextran sulfate and fucoidin, had no effect on the binding of Ox-LDL to Asp-hemolysin. Surface plasmon resonance studies revealed that Ox-LDL binds with high affinity (K(D)=0.63 microg/ml) to Asp-hemolysin. We concluded that Asp-hemolysin is a specific binding protein with a high affinity for Ox-LDL, and its binding specificity is distinct from any receptor for Ox-LDL. The present studies suggest that Asp-hemolysin may bind to Ox-LDL using a mechanism different from the scavenger receptors.
authors.affiliation: Sendai Hospital of East Japan Railway Company.
authors.forename: Y
authors.initials: Y
authors.lastname: Kudo
authors.forename: Y
authors.initials: Y
authors.lastname: Fukuchi
authors.forename: T
authors.initials: T
authors.lastname: Kumagai
authors.forename: K
authors.initials: K
authors.lastname: Ebina
authors.forename: K
authors.initials: K
authors.lastname: Yokota
mesh_terms: D001232:Aspergillus fumigatus / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism*; D006460:Hemolysin Proteins / Q000378:metabolism*; D008075:Lipoproteins, HDL / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008565:Membrane Proteins; D011485:Protein Binding; D011971:Receptors, Immunologic / Q000378:metabolism; D011973:Receptors, LDL / Q000378:metabolism; D018110:Receptors, Lipoprotein; D051116:Receptors, Scavenger; D051122:Scavenger Receptors, Class B; D020349:Surface Plasmon Resonance
chemical_list: C089497:Asp-HS protein, Aspergillus fumigatus; D005656:Fungal Proteins; D006460:Hemolysin Proteins; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D008565:Membrane Proteins; D011971:Receptors, Immunologic; D011973:Receptors, LDL; D018110:Receptors, Lipoprotein; D051116:Receptors, Scavenger; C454739:Scarb1 protein, mouse; D051122:Scavenger Receptors, Class B; C032629:acetyl-LDL; C099252:oxidized low density lipoprotein