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Structure and activity of DmmA, a marine haloalkane dehalogenase.

ABSTRACT: 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, but with a substantially larger active site binding pocket, suggestive of an ability to act on bulky substrates. This enhanced cavity was shown to accept a range of linear and cyclic substrates, suggesting that DmmA will contribute to the expanding industrial applications of HLDs.

SUBMITTER: Gehret JJ

PROVIDER: S-EPMC3324768 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Structure and activity of DmmA, a marine haloalkane dehalogenase.

Gehret Jennifer J JJ Gu Liangcai L Geders Todd W TW Brown William Clay WC Gerwick Lena L Gerwick William H WH Sherman David H DH Smith Janet L JL

Protein science : a publication of the Protein Society 20120104 2

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, but with a substantially larger active site binding pocket, suggestive of an ability to act on bulky ...[more]

PMID: 22124946

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A Haloalkane Dehalogenase from a Marine Microbial Consortium Possessing Exceptionally Broad Substrate Specificity.

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