title: Biochemical and structural characterisation of a haloalkane dehalogenase from a marine Rhodobacteraceae.
abstract: A putative haloalkane dehalogenase has been identified in a marine Rhodobacteraceae and subsequently cloned and over-expressed in Escherichia coli. The enzyme has highest activity towards the substrates 1,6-dichlorohexane, 1-bromooctane, 1,3-dibromopropane and 1-bromohexane. The crystal structures of the enzyme in the native and product bound forms reveal a large hydrophobic active site cavity. A deeper substrate binding pocket defines the enzyme preference towards substrates with longer carbon chains. Arg136 at the bottom of the substrate pocket is positioned to bind the distal halogen group of extended di-halogenated substrates.
authors.affiliation: The Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK.
authors.forename: Halina R
authors.initials: HR
authors.lastname: Novak
authors.affiliation: The Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Sayer
authors.affiliation: The Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK.
authors.forename: Michail N
authors.initials: MN
authors.lastname: Isupov
authors.affiliation: Aquapharm Biodiscovery Ltd., European Centre for Marine Biotechnology, Dunstaffnage, Oban, Argyll PA37 1QA, UK.
authors.forename: Dorothee
authors.initials: D
authors.lastname: Gotz
authors.affiliation: Aquapharm Biodiscovery Ltd., European Centre for Marine Biotechnology, Dunstaffnage, Oban, Argyll PA37 1QA, UK.
authors.forename: Andrew Mearns
authors.initials: AM
authors.lastname: Spragg
authors.affiliation: The Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK. Electronic address: J.A.Littlechild@exeter.ac.uk.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Littlechild
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D003510:Cyclohexanes / Q000737:chemistry; D006846:Hydrocarbons, Halogenated / Q000737:chemistry; D006867:Hydrolases / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011407:Propane / Q000031:analogs & derivatives / Q000737:chemistry; D011485:Protein Binding; D017433:Protein Structure, Secondary; D041902:Rhodobacteraceae / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D003510:Cyclohexanes; D006846:Hydrocarbons, Halogenated; D006867:Hydrolases; C046137:haloalkane dehalogenase; D011407:Propane; C118701:1-bromohexane; C518164:1,6-dichlorohexane; C032699:1,3-dibromopropane
keywords: Catalytic activity; Haloalkane dehalogenase; Marine Rhodobacteraceae; Three-dimensional structure