title: Three-dimensional model of the honeybee venom allergen Api m 7: structural and functional insights.
abstract: Api m 7 is one of the major protease allergens of the honeybee venom. It consists of a serine protease-like (SPL) and a CUB domain. The knowledge about the structure and function of Api m 7 is limited mainly to its amino acid sequence. Three-dimensional models of the two structural domains were constructed using their amino acid sequences and the crystallographic coordinates of prophenoloxidase-activating factor (PPAF-II) as a template for the SPL domain and the coordinates of porcine spermadhesin PSP-II for the CUB domain. The structural organization of Api m 7 suggests that the CUB domain is involved in interactions with natural substrates while the SPL domain probably activates zymogens. IgE epitopes and antigenic sites were predicted. Api m 7 shows structural and functional similarity to the members of the PPAF-II family. Possible substrates, function and evolution of the enzyme are discussed in the paper.
authors.affiliation: Institute of Biochemistry and Molecular Biology, University of Hamburg, Laboratory of Structural Biology of Infection and Inflammation, c/o DESY, Notkestrasse 85, Building 22a, 22603 Hamburg, Germany.
authors.forename: Dessislava
authors.initials: D
authors.lastname: Georgieva
authors.forename: Kerstin
authors.initials: K
authors.lastname: Greunke
authors.forename: Christian
authors.initials: C
authors.lastname: Betzel
mesh_terms: D000485:Allergens / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001514:Bee Venoms / Q000276:immunology*; D001516:Bees / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D001665:Binding Sites / Q000235:genetics; D000939:Epitopes / Q000737:chemistry / Q000378:metabolism; D007073:Immunoglobulin E / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D057057:Serine Proteases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D000485:Allergens; D001514:Bee Venoms; D000939:Epitopes; D007073:Immunoglobulin E; C551722:Api m 7 allergen, Apis mellifera; D057057:Serine Proteases