Molecular characterization of the PceA reductive dehalogenase of desulfitobacterium sp. strain Y51.
The tetrachloroethene (PCE) reductive dehalogenase (encoded by the pceA gene and designated PceA dehalogenase) of Desulfitobacterium sp. strain Y51 was purified and characterized. The expression of the enzyme was highly induced in the presence of PCE and trichloroethene (TCE). The purified enzyme catalyzed the reductive dehalogenation of PCE via TCE to cis-1,2-dichloroethene at a specific activity of 113.6 nmol x min(-1) x mg of protein(-1). The apparent K(m) values for PCE and TCE were 105.7 and 535.3 microM, respectively. Chlorinated ethenes other than PCE and TCE were not dehalogenated. However, the enzyme exhibited dehalogenation activity for various chlorinated ethanes such as hexachloroethane, pentachloroethane, 1,1,1,2-tetrachloroethane, and 1,1,2,2-tetrachloroethane. The pceA gene of Desulfitobacterium sp. strain Y51 was identified in a 2.8-kb DNA fragment and used to express the protein in Escherichia coli for the preparation of antibodies. Immunoblot analyses located PceA in the periplasm of the cell.
Suyama
Akiko
A
Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581. Towakagaku Co., Ltd., Hiroshima 730-0841, Japan.
Yamashita
Masaki
M
Yoshino
Sadazo
S
Furukawa
Kensuke
K
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D004926:Escherichia coli / Q000235:genetics; D006094:Gram-Positive Bacteria / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid
D010088:Oxidoreductases; C112990:tetrachloroethene dehalogenase