Kinetic Characterization and X-ray Structure of a Mutant of Haloalkane Dehalogenase with Higher Catalytic Activity and Modified Substrate Range†,‡
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چکیده
منابع مشابه
Kinetic characterization and X-ray structure of a mutant of haloalkane dehalogenase with higher catalytic activity and modified substrate range.
Conversion of halogenated aliphatics by haloalkane dehalogenase proceeds via the formation of a covalent alkyl-enzyme intermediate which is subsequently hydrolyzed by water. In the wild type enzyme, the slowest step for both 1,2-dichloroethane and 1,2-dibromoethane conversion is a unimolecular enzyme isomerization preceding rapid halide dissociation. Phenylalanine 172 is located in a helix-loop...
متن کاملKinetic analysis and X-ray structure of haloalkane dehalogenase with a modified halide-binding site.
Haloalkane dehalogenase (DhlA) catalyzes the hydrolysis of haloalkanes via an alkyl-enzyme intermediate. Trp175 forms a halogen/halide-binding site in the active-site cavity together with Trp125. To get more insight in the role of Trp175 in DhlA, we mutated residue 175 and explored the kinetics and X-ray structure of the Trp175Tyr enzyme. The mutagenesis study indicated that an aromatic residue...
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Structure and activity of DmmA, a marine haloalkane dehalogenase.
DmmA is a haloalkane dehalogenase (HLD) identified and characterized from the metagenomic DNA of a marine microbial consortium. Dehalogenase activity was detected with 1,3-dibromopropane as substrate, with steady-state kinetic parameters typical of HLDs (K(m) = 0.24 ± 0.05 mM, k(cat) = 2.4 ± 0.1 s(-1) ). The 2.2-Å crystal structure of DmmA revealed a fold and active site similar to other HLDs...
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ژورنال
عنوان ژورنال: Biochemistry
سال: 1996
ISSN: 0006-2960,1520-4995
DOI: 10.1021/bi961151a