| Autor: |
Fraaije, Marco W., Wu, Jin, Heuts, Dominic P. H., Van Hellemond, Erik W., Lutje Spelberg, Jeffrey H., Janssen, Dick B. |
| Předmět: |
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| Zdroj: |
Applied Microbiology & Biotechnology; Feb2005, Vol. 66 Issue 4, p393-400, 8p, 2 Black and White Photographs, 1 Diagram, 1 Chart, 1 Graph |
| Abstrakt: |
Baeyer-Villiger monooxygenases represent useful biocatalytic tools, as they can catalyze reactions which are difficult to achieve using chemical means. However, only a limited number of these atypical monooxygenases are available in recombinant form. Using a recently described protein sequence motif, a putative Baeyer-Villiger monooxygenase (BVMO) was identified in the genome of the thermophilic actinomyceteThermobifida fusca. Heterologous expression of the respective protein inEscherichia coliand subsequent enzyme characterization showed that it indeed represents a BVMO. The NADPH-dependent and FAD-containing monooxygenase is active with a wide range of aromatic ketones, while aliphatic substrates are also converted. The best substrate discovered so far is phenylacetone (kcat = 1.9 s-1,KM = 59 µM). The enzyme exhibits moderate enantioselectivity with a-methylphenylacetone (enantiomeric ratio of 7). In addition to Baeyer-Villiger reactions, the enzyme is able to perform sulfur oxidations. Different from all known BVMOs, this newly identified biocatalyst is relatively thermostable, displaying an activity half-life of 1 day at 52°C. This study demonstrates that, using effective annotation tools, genomes can efficiently be exploited as a source of novel BVMOs. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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