title: Insights into substrate binding and catalysis in bacterial type I dehydroquinase.
abstract: Structural, biochemical and computational studies to study substrate binding and the role of the conserved residues of the DHQ1 (type I dehydroquinase) enzyme active site are reported in the present paper. The crystal structure of DHQ1 from Salmonella typhi in complex with (2R)-2-methyl-3-dehydroquinic acid, a substrate analogue, was solved at 1.5 Å. The present study reveals a previously unknown key role for conserved Glu46, Phe145 and Met205 and Gln236, Pro234 and Ala233 residues, with the latter three being located in the flexible substrate-covering loop. Gln236 was shown to be responsible for the folding of this loop and for the dramatic reduction of its flexibility, which triggers active site closure. Glu46 was found to be key in bringing the substrate close to the lysine/histidine catalytic pocket to initiate catalysis. The present study could be useful in the rational design of inhibitors of this challenging and recognized target for the development of novel herbicides and antimicrobial agents.
authors: *Centro Singular de Investigación en Química Biológica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, calle Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain.
authors: María
authors: M
authors: Maneiro
authors: *Centro Singular de Investigación en Química Biológica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, calle Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain.
authors: Antonio
authors: A
authors: Peón
authors: *Centro Singular de Investigación en Química Biológica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, calle Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain.
authors: Emilio
authors: E
authors: Lence
authors: †Departamento de Bioquímica y Biología Molecular, Centro Singular de Investigación en Química Biológica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors: José M
authors: JM
authors: Otero
authors: ‡Departamento de Estructura de Macromoléculas, Centro Nacional de Biotecnología (CSIC), Campus Cantoblanco, 28049 Madrid, Spain.
authors: Mark J
authors: MJ
authors: Van Raaij
authors: §Institute of Cell and Molecular Biosciences, Medical School, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4HH, U.K.
authors: Paul
authors: P
authors: Thompson
authors: §Institute of Cell and Molecular Biosciences, Medical School, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4HH, U.K.
authors: Alastair R
authors: AR
authors: Hawkins
authors: *Centro Singular de Investigación en Química Biológica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, calle Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain.
authors: Concepción
authors: C
authors: González-Bello
mesh_terms: D000595:Amino Acid Sequence; D002384:Catalysis; D020134:Catalytic Domain; D003460:Crystallization; D018360:Crystallography, X-Ray; D006836:Hydro-Lyases / Q000378:metabolism*; D007700:Kinetics; D056004:Molecular Dynamics Simulation; D012485:Salmonella typhi / Q000201:enzymology; D013329:Structure-Activity Relationship
chemical_list: D006836:Hydro-Lyases; C020000:3-dehydroquinate dehydratase