title: Dehalogenimonas sp. Strain WBC-2 Genome and Identification of Its trans-Dichloroethene Reductive Dehalogenase, TdrA.
abstract: The Dehalogenimonas population in a dechlorinating enrichment culture referred to as WBC-2 was previously shown to be responsible for trans-dichloroethene (tDCE) hydrogenolysis to vinyl chloride (VC). In this study, blue native polyacrylamide gel electrophoresis (BN-PAGE) followed by enzymatic assays and protein identification using liquid chromatography coupled with mass spectrometry (LC-MS/MS) led to the functional characterization of a novel dehalogenase, TdrA. This new reductive dehalogenase (RDase) catalyzes the dechlorination of tDCE to VC. A metagenome of the WBC-2 culture was sequenced, and a complete Dehalogenimonas genome, only the second Dehalogenimonas genome to become publicly available, was closed. The tdrA dehalogenase found within the Dehalogenimonas genome appears to be on a genomic island similar to genomic islands found in Dehalococcoides. TdrA itself is most similar to TceA from Dehalococcoides sp. strain FL2 with 76.4% amino acid pairwise identity. It is likely that the horizontal transfer of rdhA genes is not only a feature of Dehalococcoides but also a feature of other Dehalococcoidia, including Dehalogenimonas. A set of primers was developed to track tdrA in WBC-2 subcultures maintained on different electron acceptors. This newest dehalogenase is an addition to the short list of functionally defined RDases sharing the usual characteristic motifs (including an AB operon, a TAT export sequence, two iron-sulfur clusters, and a corrinoid binding domain), substrate flexibility, and evidence for horizontal gene transfer within the Dehalococcoidia.
authors.affiliation: Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Olivia
authors.initials: O
authors.lastname: Molenda
authors.affiliation: Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Quaile
authors.affiliation: Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada elizabeth.edwards@utoronto.ca.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Edwards
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D041862:Chloroflexi / Q000737:chemistry / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D005025:Ethylene Dichlorides / Q000378:metabolism; D016680:Genome, Bacterial; D006867:Hydrolases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D063347:Native Polyacrylamide Gel Electrophoresis; D009876:Operon; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; D005025:Ethylene Dichlorides; D006867:Hydrolases