脱硫脱硫弧菌属菌株Y51的PceA还原脱卤酶的分子特征
Molecular characterization of the PceA reductive dehalogenase of desulfitobacterium sp. strain Y51.
作者信息
Suyama Akiko, Yamashita Masaki, Yoshino Sadazo, Furukawa Kensuke
机构信息
Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581. Towakagaku Co., Ltd., Hiroshima 730-0841, Japan.
出版信息
J Bacteriol. 2002 Jul;184(13):3419-25. doi: 10.1128/JB.184.13.3419-3425.2002.
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.
对脱硫脱硫弧菌属菌株Y51的四氯乙烯（PCE）还原脱卤酶（由pceA基因编码，称为PceA脱卤酶）进行了纯化和特性鉴定。该酶的表达在PCE和三氯乙烯（TCE）存在下被高度诱导。纯化后的酶催化PCE经TCE还原脱卤生成顺式-1,2-二氯乙烯，比活性为113.6 nmol·min⁻¹·mg蛋白质⁻¹。PCE和TCE的表观K(m)值分别为105.7和535.3 μM。除PCE和TCE外的其他氯代乙烯不发生脱卤反应。然而，该酶对各种氯代乙烷如六氯乙烷、五氯乙烷、1,1,1,2-四氯乙烷和1,1,2,2-四氯乙烷表现出脱卤活性。在一个2.8 kb的DNA片段中鉴定出脱硫脱硫弧菌属菌株Y51的pceA基因，并用于在大肠杆菌中表达该蛋白以制备抗体。免疫印迹分析表明PceA位于细胞周质中。
Zotero 插件