title: Structural studies of prephenate dehydratase from Mycobacterium tuberculosis H37Rv by SAXS, ultracentrifugation, and computational analysis.
abstract: Tuberculosis (TB) is one of the most common infectious diseases known to man and responsible for millions of human deaths in the world. The increasing incidence of TB in developing countries, the proliferation of multidrug resistant strains, and the absence of resources for treatment have highlighted the need of developing new drugs against TB. The shikimate pathway leads to the biosynthesis of chorismate, a precursor of aromatic amino acids. This pathway is absent from mammals and shown to be essential for the survival of Mycobacterium tuberculosis, the causative agent of TB. Accordingly, enzymes of aromatic amino acid biosynthesis pathway represent promising targets for structure-based drug design. The first reaction in phenylalanine biosynthesis involves the conversion of chorismate to prephenate, catalyzed by chorismate mutase. The second reaction is catalyzed by prephenate dehydratase (PDT) and involves decarboxylation and dehydratation of prephenate to form phenylpyruvate, the precursor of phenylalanine. Here, we describe utilization of different techniques to infer the structure of M. tuberculosis PDT (MtbPDT) in solution. Small angle X-ray scattering and ultracentrifugation analysis showed that the protein oligomeric state is a tetramer and MtbPDT is a flat disk protein. Bioinformatics tools were used to infer the structure of MtbPDT. A molecular model for MtbPDT is presented and molecular dynamics simulations indicate that MtbPDT is stable. Experimental and molecular modeling results were in agreement and provide evidence for a tetrameric state of MtbPDT in solution.
authors.affiliation: Programa de Pós Graduação em Genética e Biologia Molecular, Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre-RS, Brazil.
authors.forename: Ana Luiza
authors.initials: AL
authors.lastname: Vivan
authors.forename: Rafael Andrade
authors.initials: RA
authors.lastname: Caceres
authors.forename: Jose Ramon Beltran
authors.initials: JR
authors.lastname: Abrego
authors.forename: Júlio César
authors.initials: JC
authors.lastname: Borges
authors.forename: João
authors.initials: J
authors.lastname: Ruggiero Neto
authors.forename: Carlos H I
authors.initials: CH
authors.lastname: Ramos
authors.forename: Walter Filgueira
authors.initials: WF
authors.lastname: de Azevedo
authors.forename: Luiz Augusto
authors.initials: LA
authors.lastname: Basso
authors.forename: Diógenes Santiago
authors.initials: DS
authors.lastname: Santos
mesh_terms: D003198:Computer Simulation; D008958:Models, Molecular; D009169:Mycobacterium tuberculosis / Q000201:enzymology*; D011302:Prephenate Dehydratase / Q000737:chemistry*; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry; D053838:Scattering, Small Angle; D014461:Ultracentrifugation; D014961:X-Ray Diffraction
chemical_list: D011994:Recombinant Proteins; D011302:Prephenate Dehydratase