title: Reductive dehalogenation of brominated ethenes by Sulfurospirillum multivorans and Desulfitobacterium hafniense PCE-S.
abstract: Sulfurospirillum multivorans and Desulfitobacterium hafniense PCE-S are anaerobes that can utilize tetrachloroethene (PCE) as an electron acceptor in their energy metabolism. The end-product of PCE reduction for both organisms is cis-1,2-dichloroethene, which is formed via trichloroethene as the intermediate. The bacteria were able to dehalogenate cis- and trans-1,2-dibromoethene (cDBE and tDBE) in growing cultures and cell extracts. Dibromoethene supported growth of both organisms. The organisms debrominated cDBE and tDBE to vinyl bromide (VB); D. hafniense PCE-S also produced ethene in addition to VB. The PCE reductive dehalogenases (PCE dehalogenases) of S. multivorans and D. hafniense PCE-S mediated the debromination of tribromoethene (TBE) and both isomers of 1,2-DBE, indicating that this enzyme was responsible for the reductive dehalogenation of brominated ethenes. cDBE, tDBE, 1,1-DBE and VB were formed upon TBE debromination; VB was the major end-product. The PCE dehalogenase of D. hafniense PCE-S also formed ethene. With the purified enzymes from both organisms the kinetic properties of dehalogenation of brominated alkenes were studied and compared with those of their chlorinated analogues.
authors.affiliation: Department of Applied and Ecological Microbiology, Institute of Microbiology, Friedrich Schiller University, Philosophenweg 12, 07743 Jena, Germany.
authors.forename: Lidan
authors.initials: L
authors.lastname: Ye
authors.forename: Anke
authors.initials: A
authors.lastname: Schilhabel
authors.forename: Stefan
authors.initials: S
authors.lastname: Bartram
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Boland
authors.forename: Gabriele
authors.initials: G
authors.lastname: Diekert
mesh_terms: D001421:Bacteria, Anaerobic / Q000201:enzymology / Q000378:metabolism; D045858:Desulfitobacterium / Q000201:enzymology* / Q000254:growth & development; D004000:Dichloroethylenes / Q000378:metabolism; D004734:Energy Metabolism; D020565:Epsilonproteobacteria / Q000201:enzymology*; D005030:Ethylenes / Q000378:metabolism; D054879:Halogenation; D006842:Hydrocarbons, Brominated / Q000378:metabolism*; D010088:Oxidoreductases / Q000378:metabolism; D013750:Tetrachloroethylene / Q000378:metabolism; D014241:Trichloroethylene / Q000378:metabolism
chemical_list: D004000:Dichloroethylenes; D005030:Ethylenes; D006842:Hydrocarbons, Brominated; D014241:Trichloroethylene; C036216:ethylene; D010088:Oxidoreductases; C112990:tetrachloroethene dehalogenase; D013750:Tetrachloroethylene; C035384:1,2-dichloroethylene