tailieunhanh - Báo cáo khoa hoc : Crystal structure of Cu ⁄ Zn superoxide dismutase from Taenia solium reveals metal-mediated self-assembly

Taenia soliumis the cestode responsible for porcine and human cysticercosis. The ability of this parasite to establish itself in the host is related to its eva-sion of the immune response and its antioxidant defence system. The latter includes enzymes such as cytosolic Cu⁄Zn superoxide dismutase. | IFEBS Journal Crystal structure of Cu Zn superoxide dismutase from Taenia solium reveals metal-mediated self-assembly Alejandra Hernandez-Santoyo1 Abraham Landa2 Edith Gonzalez-Mondragon2 Martha Pedraza-Escalona1 Ricardo Parra-Unda2 and Adela Rodriguez-Romero1 1 Institute de Quimica Universidad NacionalAutonoma de Mexico Mexico 2 Departamento de Microbiologia y Parasitologia Facultad de Medicina Universidad NacionalAutonoma de Mexico Mexico Keywords crystal structure metal-mediated self-assembly superoxide dismutase Taenia solium Correspondence A. Hernandez-Santoyo A. Rodriguez-Romero Instituto de Quimica Universidad NacionalAutonoma de Mexico Mexico 04510 DF Mexico Fax 52 55 56162217 Tel 52 55 56224568 E-mail hersan@ adela@ Received 20 July 2010 revised 14 June 2011 accepted 13 July 2011 doi Taenia solium is the cestode responsible for porcine and human cysticercosis. The ability of this parasite to establish itself in the host is related to its evasion of the immune response and its antioxidant defence system. The latter includes enzymes such as cytosolic Cu Zn superoxide dismutase. In this article we describe the crystal structure of a recombinant T. solium Cu Zn superoxide dismutase representing the first structure of a protein from this organism. This enzyme shows a different charge distribution at the entrance of the active channel when compared with human Cui Zn superoxide dismutase giving it interesting properties that may allow the design of specific inhibitors against this cestode. The overall topology is similar to other superoxide dismutase structures however there are several His and Glu residues on the surface of the protein that coordinate metal ions both intra- and intermolecularly. Interestingly one of these ions located on the b2 strand establishes a metal-mediated intermolecular b P interaction including a symmetry-related molecule. The factors responsible for the abnormal .