Hynková K, Nagata Y, Takagi M, Damborský J
Department of Environmental Chemistry and Ecotoxicology, Masaryk University, Brno, Czech Republic.
FEBS Lett. 1999 Mar 5;446(1):177-81. doi: 10.1016/s0014-5793(99)00199-4.
The haloalkane dehalogenase from Sphingomonas paucimobilis UT26 (LinB) is the enzyme involved in the gamma-hexachlorocyclohexane degradation. This enzyme hydrolyses a broad range of halogenated aliphatic compounds via an alkyl-enzyme intermediate. LinB is believed to belong to the family of alpha/beta-hydrolases which employ a catalytic triad, i.e. nucleophile-histidine-acid, during the catalytic reaction. The position of the catalytic triad within the sequence of LinB was probed by a site-directed mutagenesis. The catalytic triad residues of the haloalkane dehalogenase LinB are proposed to be D108, H272 and E132. The topological location of the catalytic acid (E132) is after the beta-strand six which corresponds to the location of catalytic acid in the pancreatic lipase, but not in the haloalkane dehalogenase of Xanthobacter autotrophicus GJ10 which contains the catalytic acid after the beta-strand seven.
少动鞘氨醇单胞菌UT26的卤代烷脱卤酶（LinB）是参与γ-六氯环己烷降解的酶。该酶通过烷基-酶中间体水解多种卤代脂肪族化合物。LinB被认为属于α/β-水解酶家族，在催化反应中使用催化三联体，即亲核试剂-组氨酸-酸。通过定点诱变探究了催化三联体在LinB序列中的位置。卤代烷脱卤酶LinB的催化三联体残基被认为是D108、H272和E132。催化酸（E132）的拓扑位置在β-链六之后，这与胰脂肪酶中催化酸的位置相对应，但与自养黄色杆菌GJ10的卤代烷脱卤酶不同，后者的催化酸在β-链七之后。
