title: Discovery and characterization of thermophilic limonene-1,2-epoxide hydrolases from hot spring metagenomic libraries.
abstract: The epoxide hydrolases (EHs) represent an attractive option for the synthesis of chiral epoxides and 1,2-diols which are valuable building blocks for the synthesis of several pharmaceutical compounds. A metagenomic approach has been used to identify two new members of the atypical EH limonene-1,2-epoxide hydrolase (LEH) family of enzymes. These two LEHs (Tomsk-LEH and CH55-LEH) show EH activities towards different epoxide substrates, differing in most cases from those previously identified for Rhodococcus erythropolis (Re-LEH) in terms of stereoselectivity. Tomsk-LEH and CH55-LEH, both from thermophilic sources, have higher optimal temperatures and apparent melting temperatures than Re-LEH. The new LEH enzymes have been crystallized and their structures solved to high resolution in the native form and in complex with the inhibitor valpromide for Tomsk-LEH and poly(ethylene glycol) for CH55-LEH. The structural analysis has provided insights into the LEH mechanism, substrate specificity and stereoselectivity of these new LEH enzymes, which has been supported by mutagenesis studies.
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare, C.N.R., Milano, Italy.|University of Copenhagen, Denmark.
authors.forename: Erica Elisa
authors.initials: EE
authors.lastname: Ferrandi
authors.affiliation: The Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Sciences, University of Exeter, 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, UK.
authors.forename: Michail N
authors.initials: MN
authors.lastname: Isupov
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare, C.N.R., Milano, Italy.
authors.forename: Celeste
authors.initials: C
authors.lastname: Annovazzi
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare, C.N.R., Milano, Italy.
authors.forename: Carlotta
authors.initials: C
authors.lastname: Marchesi
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare, C.N.R., Milano, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Iacobone
authors.affiliation: University of Copenhagen, Denmark.
authors.forename: Xu
authors.initials: X
authors.lastname: Peng
authors.affiliation: Winogradsky Institute of Microbiology of the Russian Academy of Sciences, Moscow, Russia.
authors.forename: Elizaveta
authors.initials: E
authors.lastname: Bonch-Osmolovskaya
authors.affiliation: Sigma Aldrich, Buchs, Switzerland.
authors.forename: Roland
authors.initials: R
authors.lastname: Wohlgemuth
authors.affiliation: The Henry Wellcome Building for Biocatalysis, Biosciences, College of Life and Environmental Sciences, University of Exeter, UK.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Littlechild
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare, C.N.R., Milano, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Monti
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D020134:Catalytic Domain; D003001:Cloning, Molecular; D004851:Epoxide Hydrolases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D006358:Hot Temperature; D054892:Metagenome; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D014867:Water
chemical_list: D001426:Bacterial Proteins; D014867:Water; D004851:Epoxide Hydrolases; C115926:limonene-1,2-epoxide hydrolase
keywords: industrial biocatalysis; limonene-1,2-epoxide hydrolases; metagenomics; protein structure; stereoselectivity