Asymmetric whole cell biotransformations in biphasic ionic liquid/water-systems by use of recombinant Escherichia coli with intracellular cofactor regeneration

Bräutigam, Stefan; Bringer-Meyer, Stephanie; Weuster‐Botz, Dirk

doi:10.1016/j.tetasy.2007.08.003

Cited by 85 publications

(66 citation statements)

References 18 publications

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“…Analysis of educts and products was performed by chiral gas chromatography using the following columns: BGB-174 (BGB-Analytics, Schlossboeckelheim, Germany) for measurement of 1,1,1-trifluoroacetone and substituted acetophenones as described previously (3,8), BGB-175 (BGB-Analytics, Schlossboeckelheim, Germany) for 2-octanone, and Lipodex-E (Macharey-Nagel, Dü-ren, Germany) for ethyl 4-chloroacetoacetate and ethylbenzoylacetate.…”

Section: Chemicals and Enzymesmentioning

confidence: 99%

Identification, Cloning, and Characterization of a Novel Ketoreductase from the Cyanobacterium Synechococcus sp. Strain PCC 7942

Hölsch

Havel

Haslbeck

et al. 2008

Appl Environ Microbiol

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A new ketoreductase useful for asymmetric synthesis of chiral alcohols was identified in the cyanobacterium Synechococcus sp. strain PCC 7942. Mass spectrometry of trypsin-digested peptides identified the protein as 3-ketoacyl-[acyl-carrier-protein] reductase (KR) (EC 1.1.1.100). The gene, referred to as fabG, was cloned, functionally expressed in Escherichia coli, and subsequently purified to homogeneity. The enzyme displayed a temperature optimum at 44°C and a broad pH optimum between pH 7 and pH 9. The NADPH-dependent KR was able to asymmetrically reduce a variety of prochiral ketones with good to excellent enantioselectivities (>99.8%). The KR showed particular high specific activity for asymmetric reduction of ethyl 4-chloroacetoacetate (38.29 ؎ 2.15 U mg

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Section: Chemicals and Enzymesmentioning

confidence: 99%

Identification, Cloning, and Characterization of a Novel Ketoreductase from the Cyanobacterium Synechococcus sp. Strain PCC 7942

Hölsch

Havel

Haslbeck

et al. 2008

Appl Environ Microbiol

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“…However, the biocatalyst was slightly more effective in the presence of the ionic liquid BMpl NTf 2 . Therefore, these parameters (log D and biocompatability) were not sufficient for an estimation of the best suited IL for the entire reaction system which confirmed results previously obtained by Bräutigam et al (2007). [14] Conclusions It was demonstrated that benzaldehyde exerted a much stronger inhibitory effect than HCN on the nitrilase activity of recombinant E. coli cells.…”

Section: Discussionmentioning

confidence: 56%

“…[9] There are also only very few publications which described the utilisation of recombinant E. coli strains for biotransformation reactions in the presence of ionic liquids. [8,14,15] Thus, Bräutigam et al (2007) demonstrated the asym- Table 4. Conversion of benzaldehyde and HCN by resting cells of E. coli JM109A C H T U N G T R E N N U N G (pIK9)(pJOE5361.1) in a two-phase system with the ionic liquid BMim NTf 2.…”

Section: Discussionmentioning

confidence: 95%

“…[14] From the distribution coefficients given by the authors it can be deduced that in these experiments the substrate (ketones) and the products (alcohols) will preferentially partition into the ionic liquid phases. Subsequently, it was demonstrated that ketone concentrations of 600 mM (in the ionic liquid phases) could be converted by the cells with yields of about 40-60%.…”

Section: Discussionmentioning

confidence: 99%

“…Subsequently, it was demonstrated that ketone concentrations of 600 mM (in the ionic liquid phases) could be converted by the cells with yields of about 40-60%. [14] In addition, Cornmell et al (2008) utilised a recombinant E. coli strain expressing ringhydroxylating dioxygenases for the conversion of toluene to toluene cis-glycol in the presence of ionic liquids and Schroer et al (2007) studied the reduction of 1-phenyl-2-propanone to the chiral alcohol in the presence of an ionic liquid by a recombinantly expressed alcohol dehydrogenase using 2-propanol as ultimate source of reduction equivalents. [8,15] The reaction system described in the present manuscript differs significantly from most of the previously decribed two-phase systems applying ILs because in these preceding studies the organic substrates and the products usually accumulated in the IL phase.…”

Section: Discussionmentioning

confidence: 99%

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Application of a Recombinant Escherichia coli Whole‐Cell Catalyst Expressing Hydroxynitrile Lyase and Nitrilase Activities in Ionic Liquids for the Production of (S)‐Mandelic Acid and (S)‐Mandeloamide

Baum

Rantwijk

2012

Adv Synth Catal

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The conversion of benzaldehyde and cyanide into mandelic acid and mandeloamide by a recombinant Escherichia coli strain which simultaneously expressed an (S)-hydroxynitrile lyase (oxynitrilase) from cassava (Manihot esculenta) and an aryl-A C H T U N G T R E N N U N G acetonitrilase from Pseudomonas fluorescens EBC191 was studied. Benzaldehyde exhibited a pronounced inhibitory effect on the nitrilase activity in concentrations ! 25 mM. Therefore, it was tested if two-phase systems consisting of a buffered aqueous phase and the ionic liquid 1-butyl-1-pyrrolidinium bis(trifluoromethanesulfonyl)imide (BMpl NTf 2 ) or 1-butyl-3-methylimidazolium hexafluorophosphate (BMim PF 6 ) could be used for the intended biotransformation. The distribution coefficients of the substrates, intermediates and products of the reaction were determined and it was found that BMpl NTf 2 and BMim PF 6 were highly efficient as substrate reservoirs for benzaldehyde. The recombinant E. coli strain was active in the presence of BMpl NTf 2 or BMim PF 6 phases and converted benzaldehyde and cyanide into mandelic acid and mandeloamide. The two-phase systems allowed the conversion of benzaldehyde dissolved in the ionic liquids to a concentration of 700 mM with product yields (= sum of mandelic acid and mandeloamide) of 87-100%. The cells were slightly more effective in the presence of BMpl NTf 2 than in the presence of BMim PF 6 . In both two-phase systems benzaldehyde and cyanide were converted into (S)-mandeloamide and (S)-mandelic acid with enantiomeric excesses ! 94%. The recombinant E. coli cells formed, in the two-phase systems with ionic liquids and increased substrate concentrations, higher relative amounts of mandelo-A C H T U N G T R E N N U N G amide than in a purely aqueous system with lower substrate concentrations.

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Dehydrogenase

Sánchez

Barrena

2009

Encyclopedia of Industrial Biotechnology

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Dehydrogenase is a general term describing a wide subgroup of oxidoreductases, enzymes that participate in reactions involving electron transfer. Because electron transfer implies the presence of an electron donor and an electron acceptor, and the chemical typology of these substances can be very different, the dehydrogenase class includes a large number of enzymes. Dehydrogenases are produced by a large number of microorganisms and other living organisms. Numerous applications have been described for them, the most advanced being their use in chiral resolution after some immobilization procedure. Also, interest in using dehydrogenase activity to monitor the global aerobic activity in environmental biotechnology has grown in recent years. In this application, dehydrogenase activity is used to monitor the biodegradation process, as it is related to the metabolic reactions producing energy in the form of ATP through the oxidation of organic compounds. It has been successfully applied to the biological treatment of wastewater and solid wastes and soil bioremediation. Specific dehydrogenase activity can be determined by a typical enzyme substrate–specific reaction. Nevertheless, values of overall dehydrogenase activity are also important because this value can often be related to the aerobic activity in ill‐defined (unsorted) media. In this case, two main substrates are typically used to accept electrons from dehydrogenase enzymes, triphenyl‐tetrazolium chloride (TTC) and 2‐( p ‐iodophenyl)‐3( p ‐nitrophenyl)‐5‐phenyl tetrazolium chloride (INT); the resulting reduced products are forms of red‐colored formazan (TPF and INTF, respectively).

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Asymmetric whole cell biotransformations in biphasic ionic liquid/water-systems by use of recombinant Escherichia coli with intracellular cofactor regeneration

Cited by 85 publications

References 18 publications

Identification, Cloning, and Characterization of a Novel Ketoreductase from the Cyanobacterium Synechococcus sp. Strain PCC 7942

Identification, Cloning, and Characterization of a Novel Ketoreductase from the Cyanobacterium Synechococcus sp. Strain PCC 7942

Application of a Recombinant Escherichia coli Whole‐Cell Catalyst Expressing Hydroxynitrile Lyase and Nitrilase Activities in Ionic Liquids for the Production of (S)‐Mandelic Acid and (S)‐Mandeloamide

Dehydrogenase

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