title: Structural resolution of the complex between a fungal polygalacturonase and a plant polygalacturonase-inhibiting protein by small-angle X-ray scattering.
abstract: We report here the low-resolution structure of the complex formed by the endo-polygalacturonase from Fusarium phyllophilum and one of the polygalacturonase-inhibiting protein from Phaseolus vulgaris after chemical cross-linking as determined by small-angle x-ray scattering analysis. The inhibitor engages its concave surface of the leucine-rich repeat domain with the enzyme. Both sides of the enzyme active site cleft interact with the inhibitor, accounting for the competitive mechanism of inhibition observed. The structure is in agreement with previous site-directed mutagenesis data and has been further validated with structure-guided mutations and subsequent assay of the inhibitory activity. The structure of the complex may help the design of inhibitors with improved or new recognition capabilities to be used for crop protection.
authors.affiliation: Dipartimento di Biologia e Biotecnologie C. Darwin, Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza Università di Roma, 00185 Rome, Italy.
authors.forename: Manuel
authors.initials: M
authors.lastname: Benedetti
authors.forename: Claudia
authors.initials: C
authors.lastname: Leggio
authors.forename: Luca
authors.initials: L
authors.lastname: Federici
authors.forename: Giulia
authors.initials: G
authors.lastname: De Lorenzo
authors.forename: Nicolae Viorel
authors.initials: NV
authors.lastname: Pavel
authors.forename: Felice
authors.initials: F
authors.lastname: Cervone
mesh_terms: D020134:Catalytic Domain; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism; D005670:Fusarium / Q000201:enzymology; D054884:Host-Pathogen Interactions; D016297:Mutagenesis, Site-Directed; D027805:Phaseolus / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011096:Polygalacturonase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D011487:Protein Conformation; D053838:Scattering, Small Angle; D014961:X-Ray Diffraction
chemical_list: D004791:Enzyme Inhibitors; D005656:Fungal Proteins; C081479:PGIP protein, plant; D010940:Plant Proteins; D011096:Polygalacturonase