title: Expression, purification and crystallization of MnSOD from Arabidopsis thaliana.
abstract: Manganese superoxide dismutase (MnSOD) is an essential primary antioxidant enzyme. MnSOD plays an important role in plant tolerance to abiotic stress and is a target candidate for increasing stress tolerance in crop plants. Although the structure and kinetic parameters of MnSODs from several organisms have been determined, this information is still lacking for plant MnSODs. Here, recombinant MnSOD from Arabidopsis thaliana (AtMnSOD) was expressed, purified and crystallized. A nearly complete data set could only be obtained when a total rotation range of 180° was imposed during data collection, despite the seemingly tetragonal metric of the AtMnSOD crystal diffraction. The data set extended to 1.95 Å resolution and the crystal belonged to space group P1. Molecular-replacement calculations using an ensemble of homologous SOD structures as a search model gave a unique and unambiguous solution corresponding to eight molecules in the asymmetric unit. Structural and kinetic analysis of AtMnSOD is currently being undertaken.
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, EAN, 2780-157 Oeiras, Portugal.
authors.forename: Alexandra T
authors.initials: AT
authors.lastname: Marques
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, EAN, 2780-157 Oeiras, Portugal.
authors.forename: Sandra P
authors.initials: SP
authors.lastname: Santos
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, EAN, 2780-157 Oeiras, Portugal.
authors.forename: Margarida G
authors.initials: MG
authors.lastname: Rosa
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, EAN, 2780-157 Oeiras, Portugal.
authors.forename: Mafalda A A
authors.initials: MA
authors.lastname: Rodrigues
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, EAN, 2780-157 Oeiras, Portugal.
authors.forename: Isabel A
authors.initials: IA
authors.lastname: Abreu
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, EAN, 2780-157 Oeiras, Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Frazão
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Avenida da República, EAN, 2780-157 Oeiras, Portugal.
authors.forename: Célia V
authors.initials: CV
authors.lastname: Romão
mesh_terms: D017360:Arabidopsis / Q000201:enzymology*; D003460:Crystallization; D015971:Gene Expression Regulation, Enzymologic; D013482:Superoxide Dismutase / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D013482:Superoxide Dismutase
keywords: ROS; SOD; metalloproteins; oxidative stress; plants