title: The fungal elicitor cryptogein is a sterol carrier protein.
abstract: Cryptogein is a protein secreted by the phytopathogenic pseudo-fungus, Phytophthora cryptogea. It is a basic 10 kDa hydrophilic protein having a hydrophobic pocket and three disulfide bridges. These common features with sterol carrier proteins led us to investigate its possible sterol transfer activity using the fluorescent sterol, dehydroergosterol. The results show that cryptogein has one binding site with strong affinity for dehydroergosterol. Moreover, this protein catalyzes the transfer of sterols between phospholipidic artificial membranes. This is the first evidence for the existence of an extracellular sterol carrier protein and for a molecular activity of cryptogein. This property should contribute to an understanding of the role of cryptogein in plant-microorganism interactions.
authors.affiliation: Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic.
authors.forename: V
authors.initials: V
authors.lastname: Mikes
authors.forename: M L
authors.initials: ML
authors.lastname: Milat
authors.forename: M
authors.initials: M
authors.lastname: Ponchet
authors.forename: P
authors.initials: P
authors.lastname: Ricci
authors.forename: J P
authors.initials: JP
authors.lastname: Blein
mesh_terms: D020418:Algal Proteins; D002352:Carrier Proteins / Q000378:metabolism*; D002784:Cholesterol / Q000378:metabolism*; D004875:Ergosterol / Q000031:analogs & derivatives* / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism*; D007700:Kinetics; D008081:Liposomes; D010838:Phytophthora / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
chemical_list: D020418:Algal Proteins; D002352:Carrier Proteins; D005656:Fungal Proteins; D008081:Liposomes; C061032:cryptogein protein, Phytophthora cryptogea; C010905:dehydroergosterol; D002784:Cholesterol; D004875:Ergosterol