Asymmetric Reduction of Ethyl 2-methyl 3-oxobutanoate by<i>Chlorella</i>

Kuramoto, Takayuki; Iwamoto, Kenzo; Izumi, Minoru; Kirihata, Mitsunori; Yoshizako, Fumiki

doi:10.1271/bbb.63.598

Cited by 12 publications

(2 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In terms of energy acquisition efficiency, photoautotrophic organisms appear to be the most effective biocatalytic agents ( Nakamura 2007 ). In fact, there have been several reports on asymmetric reduction using photoautotrophs such as microalgae ( Noma and Asakawa 1992 , Kuramoto et al 1999 , Nakamura et al 2000 , Utsukihara et al 2004 , Shimoda et al 2004 , Itoh et al 2005 , Utsukihara et al 2006 , Takemura et al 2009 ), plant cultured-cells ( Kojima et al 2009 ), and germinated plants ( Matsuo et al 2008 , Takeda et al 2011 ). Enzymatic systems isolated from a microalga were used in combination with NADPH (nicotinamide adenine dinucleotide phosphate) to perform a biotransformation such as biocatalytic reduction ( Shimoda and Hirata 2000 ).…”

Section: Introductionmentioning

confidence: 99%

Reduction of exogenous ketones depends upon NADPH generated photosynthetically in cells of the cyanobacterium Synechococcus PCC 7942

2011

View full text Add to dashboard Cite

Effective utilization of photosynthetic microorganisms as potential biocatalysts is favorable for the production of useful biomaterials and the reduction of atmospheric CO2. For example, biocatalytic transformations are used in the synthesis of optically active alcohols. We previously found that ketone reduction in cells of the cyanobacterium Synechococcus PCC 7942 is highly enantioselective and remarkably enhanced under light illumination. In this study, the mechanism of light-enhanced ketone reduction was investigated in detail using several inhibitors of photosynthetic electron transport and of enzymes of the Calvin cycle. It is demonstrated that light intensity and photosynthesis inhibitors significantly affect the ketone reduction activity in Synechococcus. This indicates that the reduction correlates well with photosynthetic activity. Moreover, ketone reduction in Synechococcus specifically depends upon NADPH and not NADH. These results also suggest that cyanobacteria have the potential to be utilized as biocatalytic systems for direct usage of light energy in various applications such as syntheses of useful compounds and remediation of environmental pollutants.

show abstract

Section: Introductionmentioning

confidence: 99%

Reduction of exogenous ketones depends upon NADPH generated photosynthetically in cells of the cyanobacterium Synechococcus PCC 7942

2011

View full text Add to dashboard Cite

show abstract

“…The possibility of using green algae as biocatalysts to synthesize chiral building blocks has been also investigated. For example, Yoshizako et al reported that the stereoselective reduction of various carbonyl compounds by Chlorella pyrenoidosa Chick yielded the corresponding chiral alcohols (Yoshizako et al 1992(Yoshizako et al , 1994(Yoshizako et al , 1995(Yoshizako et al , 1996(Yoshizako et al , 1998Kuramoto et al 1999). Furthermore, ethyl 2-methyl-3-oxobutanoate was exclusively reduced to the corresponding syn-(2R, 3S)-hydroxy ester by photoautotrophically cultivated Chlorella sorokiniana in the presence of glycerol (Ishihara et al 2000a(Ishihara et al , 2003.…”

Section: Introductionmentioning

confidence: 99%

Purification and characterization of a novel keto ester reductase from the green alga, Chlorella sorokiniana: comparison of enzymological properties with other microbial keto ester reductases

Ishihara

Iwai

Yoshida

et al. 2010

World J Microbiol Biotechnol

View full text Add to dashboard Cite

A novel keto ester reductase (Chlorella sorokiniana keto ester reductase, CSKER) from Chlorella sorokiniana SAG 211-8k cells was purified. The CSKER had a monomeric structure based on gel filtration chromatography (37 kDa) and SDS-polyacrylamide gel electrophoresis (34 kDa). The purified CSKER showed a high reducing activity with b-keto esters, in particular, ethyl 4-chloro-3-oxobutanoate and ethyl 2-chloro-3-oxobutanoate. However, the purified enzyme did not show any reducing activity with a-keto esters and 2-chlorobenzoylformamide (aromatic a-keto amide). The CSKER catalyzed the reduction of ethyl 4-chloro-3-oxobutanoate, ethyl 3-oxobutanoate, and methyl 3-oxobutanoate to the corresponding (R)-, (S)-, and (S)-hydroxy ester, respectively, with high enantioselectivity ([99% e.e.), respectively. Furthermore, the reduction of ethyl 2-methyl-3-oxobutanoate by CSKER exclusively yielded the corresponding syn-(2R, 3S)-hydroxy ester. The purified CSKER was inactive with NADH, used instead of NADPH. None of the keto ester-reducing enzymes already isolated from other microorganisms was identical to the CSKER. These results suggested that CSKER is a novel keto ester reductase that has not yet been reported.

show abstract

Reduction of Various Functionalities

Nakamura¹,

Matsudo²

2002

Enzyme Catalysis in Organic Synthesis

View full text Add to dashboard Cite

Asymmetric Reduction of Ethyl 2-methyl 3-oxobutanoate byChlorella

Cited by 12 publications

References 18 publications

Reduction of exogenous ketones depends upon NADPH generated photosynthetically in cells of the cyanobacterium Synechococcus PCC 7942

Reduction of exogenous ketones depends upon NADPH generated photosynthetically in cells of the cyanobacterium Synechococcus PCC 7942

Purification and characterization of a novel keto ester reductase from the green alga, Chlorella sorokiniana: comparison of enzymological properties with other microbial keto ester reductases

Reduction of Various Functionalities

Contact Info

Product

Resources

About