This capability has made them attractive biocatalysts, and extensive efforts have been devoted to both discovering and engineering these enzymes for different applications. Of the different classes of halogenases characterized to date, flavin dependent halogenases (FDHs) are most commonly associated with site-selective halogenation of electron rich arenes and enol(ate) moieties in the biosynthesis of halogenated natural products. Here, the authors describe examples of engineered flavin-dependent halogenases that catalyze halolactonization of olefins with high enantioselectivity and near-native catalytic activity. Catalytic enantioselective halocyclization of alkenes is an important bond forming tool and a key step in natural product biosynthesis, but so far no examples of the enzymatic counterpart of this reaction on simple achiral olefins have been reported. This expansion of FDH catalytic activity presages the development of a wide range of biocatalytic halogenation reactions. The structural origins of improvements imparted by mutations responsible for the emergence of halocyclase activity are discussed. Highly selective halocyclization is achieved by characterizing and mitigating the release of HOBr from the FDH active site using a combination of reaction optimization and protein engineering. Herein, we reveal that FDHs engineered to catalyze site-selective aromatic halogenation also catalyze non-native bromolactonization of olefins with high enantioselectivity and near-native catalytic proficiency. Flavin-dependent halogenases (FDHs) catalyze halogenation of arene and enol(ate) substrates. Identifying suitable enzymes that catalyze enantioselective halocyclization of simple olefins would therefore have significant synthetic value. To receive a quote to repair your defective Packard unit(s) simply complete this online form, email or call Ryan Fitzgerald at (212) 772-6992 ext.Halocyclization of alkenes is a powerful bond-forming tool in synthetic organic chemistry and a key step in natural product biosynthesis, but catalyzing halocyclization with high enantioselectivity remains a challenging task. All our Packard-17405-ID repairs include a 1 year warranty, covering both parts and labor. Our services for the Packard Packard-17405-ID include diagnostic evaluation, troubleshooting, component and board level repair, as well as complete rebuilding of the Packard-17405-ID if necessary.Įxpedited handling of our evaluations and repairs are included as a standard service for all our clients. We service and repair Packard Packard-17405-ID and related systems and components, including severely damaged and defective units. For a Packard warranty or support plan to fit your requirements, send an email to or call Ryan Fitzgerald at (212) 772-6992 ext. We offer Extended Warranty plans for your Packard Packard-17405-ID as well as On the Packard-17405-ID and related equipment. In addition to stocking the Packard Packard-17405-ID spares, we also provide Packard services Service & Support for Packard Packard-17405-ID Qualified York technicians are standing by to assist you. To receive an online quote or obtain additional information simply click here. We may have additional and new units in stock as well. This original Packard spare is refurbished and in excellent condition. We have at least quantity 1 of the Packard-17405-ID made by Packard on hand for immediate shipment. Packard Packard-17405-ID Available for Shipment Product Category: Lab Equipment, Sub Category: Other Less Packard Micromate 496 Plate Sealer, Business & Industrial, Healthcare, Lab &. Packard Micromate 496 Plate Sealer, Business & Industrial, Healthcare, Lab & Life Science, Lab Equipment.
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