title: Cloning, expression, purification, crystallization and preliminary X-ray analysis of EaLsc, a levansucrase from Erwinia amylovora.
abstract: The Gram-negative bacterium Erwinia amylovora is a destructive pathogen of Rosaceae. During infection, E. amylovora produces the exopolysaccharide levan, which contributes to the occlusion of plant vessels, causing the wilting of shoots. Levan is a fructose polymer that is synthesized by multifunctional enzymes called levansucrases. The levansucrase from E. amylovora (EaLsc) was heterologously expressed as a GST-fusion protein in Escherichia coli, purified and crystallized after tag removal. The protein crystallized in space group P21212. X-ray diffraction data were acquired to 2.77 Å resolution. The structure of the enzyme was solved by molecular replacement. The asymmetric unit contains eight enzyme molecules, giving a solvent content of 58.74% and a Matthews coefficient of 2.98 Å(3) Da(-1).
authors.affiliation: Laboratory of Bioorganic Chemistry and Crystallography, Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Caputi
authors.forename: Michele
authors.initials: M
authors.lastname: Cianci
authors.forename: Stefano
authors.initials: S
authors.lastname: Benini
mesh_terms: D003001:Cloning, Molecular / Q000379:methods; D003460:Crystallization; D044084:Erwinia amylovora / Q000201:enzymology*; D015964:Gene Expression Regulation, Bacterial; D006602:Hexosyltransferases / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D011134:Polysaccharides / Q000737:chemistry / Q000235:genetics; D014961:X-Ray Diffraction
chemical_list: D011134:Polysaccharides; D006602:Hexosyltransferases; C021513:levansucrase
keywords: Erwinia; fructooligosaccharides; fructosyltransferases; levan; levansucrases