scholarly journals Efficient chiral synthesis by Saccharomyces cerevisiae spore encapsulation of Candida parapsilosis Glu228Ser/(S)-carbonyl reductase II and Bacillus sp. YX-1 glucose dehydrogenase in organic solvents

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Jingxin Rao ◽  
Rongzhen Zhang ◽  
Hongbo Liang ◽  
Xiao-Dong Gao ◽  
Hideki Nakanishi ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Organic Solvents ◽  
Candida Parapsilosis ◽  
Glucose Dehydrogenase ◽  
Carbonyl Reductase ◽  
Bacillus Sp ◽  
Chiral Synthesis

scholarly journals Efficient production of (S)-1-phenyl-1, 2-ethanediol using xylan as co-substrate by a coupled multi-enzyme Escherichia coli system

2020 ◽  
Author(s):  
Junchao Rao ◽  
Rongzhen Zhang ◽  
Guanyu Xu ◽  
Lihong Li ◽  
Yan Xu
Keyword(s):  
Escherichia Coli ◽  
Glucose Dehydrogenase ◽  
Optical Purity ◽  
Carbonyl Reductase ◽  
Cofactor Regeneration ◽  
Efficient Production ◽  
Chiral Synthesis ◽  
E Coli ◽  
Concomitant Reduction ◽  
Different Strains

Abstract Background: ( S )-1-phenyl-1,2-ethanediol is an important chiral intermediate in the synthesis of liquid crystals and chiral biphosphines.(S)-carbonyl reductase II from Candida parapsilosis catalyzes the conversion of 2-hydroxyacetophenone to ( S )-1-phenyl-1,2-ethanediol with NADPH as a cofactor. Glucose dehydrogenase with a Ala258Phe mutation is able to catalyze the oxidation of xylose with concomitant reduction of NADP + to NADPH, while endo-β-1,4-xylanase 2 catalyzes the conversion of xylan to xylose. In the present work, the Ala258Phe glucose dehydrogenase mutant and endo-β-1,4-xylanase 2 were introduced into the ( S )-carbonyl reductase II-mediated chiral pathway to strengthen cofactor regeneration by using xylan as a naturally abundant co-substrate. Results: We constructed several coupled multi-enzyme systems by introducing ( S )-carbonyl reductase II, the A258F glucose dehydrogenase mutant and endo-β-1,4-xylanase 2 into Escherichia coli . Different strains were produced by altering the location of the encoding genes on the plasmid. Only recombinant E. coli /pET-G-S-2 expressed all three enzymes, and this strain produced ( S )-1-phenyl-1,2-ethanediol from 2-hydroxyacetophenone as a substrate and xylan as a co-substrate. The optical purity was 100% and the yield was 98.3% (6 g/L 2-HAP) under optimal conditions of 35°C, pH 6.5 and a 2:1 substrate-co-substrate ratio. The introduction of A258F glucose dehydrogenase and endo-β-1,4-xylanase 2 into the ( S )-carbonyl reductase II-mediated chiral pathway caused a 54.6% increase in yield, and simultaneously reduced the reaction time from 48 h to 28 h. Conclusions: This study demonstrates efficient chiral synthesis using a pentose as a co-substrate to enhance cofactor regeneration. This provides a new approach for enantiomeric catalysis through the inclusion of naturally abundant materials.

scholarly journals Efficient biotransformation of (S)-1-phenyl-1, 2-ethanediol using xylan as co-substrate by a coupled multi-enzyme Escherichia coli system

2020 ◽  
Author(s):  
Junchao Rao ◽  
Rongzhen Zhang ◽  
Guanyu Xu ◽  
Lihong Li ◽  
Yan Xu
Keyword(s):  
Escherichia Coli ◽  
Glucose Dehydrogenase ◽  
Optical Purity ◽  
Carbonyl Reductase ◽  
Cofactor Regeneration ◽  
Chiral Synthesis ◽  
E Coli ◽  
Concomitant Reduction ◽  
Different Strains ◽  
Encoding Genes

Abstract Background: ( S )-1-phenyl-1,2-ethanediol is an important chiral intermediate in the synthesis of liquid crystals and chiral biphosphines. ( S )-carbonyl reductase II from Candida parapsilosis catalyzes the conversion of 2-hydroxyacetophenone to ( S )-1-phenyl-1,2-ethanediol with NADPH as a cofactor. Glucose dehydrogenase with a Ala258Phe mutation is able to catalyze the oxidation of xylose with concomitant reduction of NADP + to NADPH, while endo-β-1,4-xylanase 2 catalyzes the conversion of xylan to xylose. In the present work, the Ala258Phe glucose dehydrogenase mutant and endo-β-1,4-xylanase 2 were introduced into the ( S )-carbonyl reductase II-mediated chiral pathway to strengthen cofactor regeneration by using xylan as a naturally abundant co-substrate. Results: We constructed several coupled multi-enzyme systems by introducing ( S )-carbonyl reductase II, the A258F glucose dehydrogenase mutant and endo-β-1,4-xylanase 2 into Escherichia coli . Different strains were produced by altering the location of the encoding genes on the plasmid. Only recombinant E. coli /pET-G-S-2 expressed all three enzymes, and this strain produced ( S )-1-phenyl-1,2-ethanediol from 2-hydroxyacetophenone as a substrate and xylan as a co-substrate. The optical purity was 100% and the yield was 98.3% under optimal conditions of 35°C, pH 6.5 and a 2:1 substrate-co-substrate ratio. The introduction of A258F glucose dehydrogenase and endo-β-1,4-xylanase 2 into the ( S )-carbonyl reductase II-mediated chiral pathway caused a 54.6% increase in yield, and simultaneously reduced the reaction time from 48 h to 28 h. Conclusions: This study demonstrates efficient chiral synthesis using a pentose as a co-substrate to enhance cofactor regeneration. This provides a new approach for enantiomeric catalysis through the inclusion of naturally abundant materials.

Efecto proapoptótico y antimetastásico en líneas tumorales humanas colorrectales de una proteína secretada por la bacteria Rizosférica Antártica Bacillus sp. K2I17

2019 ◽  
Author(s):  
Alequis Tomás Pavón Oro
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Deschampsia Antarctica ◽  
Bacillus Sp ◽  
E Coli ◽  
Cáncer Colorrectal

El cáncer es la segunda causa de muerte en el mundo, y específicamente en Chile el cáncer colorrectal es el único que presenta un aumento sostenido de la mortalidad en la última década. La búsqueda de nuevos agentes quimioterapeúticos anticancerígenos ha propuesto a los microorganismos extremófilos como una fuente potencial para obtener moléculas citotóxicas, que induzcan apoptosis en las células tumorales. Las condiciones extremas del continente antártico y las presiones selectivas por el espacio y los nutrientes que se producen entre los microorganismos del rizobioma de la planta Deschampsia antarctica Desv sugirieron como hipótesis que las bacterias rizosféricas aisladas en la Antártica secretan al sobrenadante de cultivo moléculas bioactivas que inhiben la invasión y proliferación de líneas tumorales humanas de origen colorrectal mediante un mecanismo apoptótico. En este sentido, el objetivo general del trabajo fue identificar y caracterizar a moléculas bioactivas con acción antinvasiva y antiproliferativa, además, determinar el mecanismo inhibitorio de la proliferación en líneas tumorales humanas de origen colorrectal. Los resultados del primer objetivo específico demostraron que los sobrenadantes de cultivo de los aislados rizosféricos antárticos K2 y MI disminuyeron la viabilidad de la línea celular de adenocarcinoma colorrectal LoVo en el ensayo de reducción metabólica del MTT. Además, como los sobrenadantes no tuvieron efecto en la viabilidad de las bacterias E. coli y Staphylococcus aureus, y tampoco en los hongos unicelulares Candida albicans y Saccharomyces cerevisiae, el resultado indicó que la actividad antiproliferativa fue selectiva hacia la línea celular LoVo.

scholarly journals Probiotic Yeasts Inhibit Virulence of Non-albicans Candida Species

mBio ◽  
2019 ◽  
Vol 10 (5) ◽  
Author(s):  
Lohith Kunyeit ◽  
Nawneet K. Kurrey ◽  
K. A. Anu-Appaiah ◽  
Reeta P. Rao
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Candida Tropicalis ◽  
Biofilm Formation ◽  
Candida Glabrata ◽  
Candida Parapsilosis ◽  
Candida Krusei ◽  
Probiotic Properties ◽  
Candida Auris ◽  
Content Type ◽  
Alternative Approach

ABSTRACT Systemic infections of Candida species pose a significant threat to public health. Toxicity associated with current therapies and emergence of resistant strains present major therapeutic challenges. Here, we report exploitation of the probiotic properties of two novel, food-derived yeasts, Saccharomyces cerevisiae (strain KTP) and Issatchenkia occidentalis (strain ApC), as an alternative approach to combat widespread opportunistic fungal infections. Both yeasts inhibit virulence traits such as adhesion, filamentation, and biofilm formation of several non-albicans Candida species, including Candida tropicalis, Candida krusei, Candida glabrata, and Candida parapsilosis as well as the recently identified multidrug-resistant species Candida auris. They inhibit adhesion to abiotic surfaces as well as cultured colon epithelial cells. Furthermore, probiotic treatment blocks the formation of biofilms of individual non-albicans Candida strains as well as mixed-culture biofilms of each non-albicans Candida strain in combination with Candida albicans. The probiotic yeasts attenuated non-albicans Candida infections in a live animal. In vivo studies using Caenorhabditis elegans suggest that exposure to probiotic yeasts protects nematodes from infection with non-albicans Candida strains compared to worms that were not exposed to the probiotic yeasts. Furthermore, application of probiotic yeasts postinfection with non-albicans Candida alleviated pathogenic colonization of the nematode gut. The probiotic properties of these novel yeasts are better than or comparable to those of the commercially available probiotic yeast Saccharomyces boulardii, which was used as a reference strain throughout this study. These results indicate that yeasts derived from food sources could serve as an effective alternative to antifungal therapy against emerging pathogenic Candida species. IMPORTANCE Non-albicans Candida-associated infections have emerged as a major risk factor in the hospitalized and immunecompromised patients. Besides, antifungal-associated complications occur more frequently with these non-albicans Candida species than with C. albicans. Therefore, as an alternative approach to combat these widespread non-albicans Candida-associated infections, here we showed the probiotic effect of two yeasts, Saccharomyces cerevisiae (strain KTP) and Issatchenkia occidentalis (ApC), in preventing adhesion and biofilm formation of five non-albicans Candida strains, Candida tropicalis, Candida krusei, Candida glabrata, Candida parapsilosis, and Candida auris. The result would influence the current trend of the conversion of conventional antimicrobial therapy into beneficial probiotic microbe-associated antimicrobial treatment.

Efficient production of an ezetimibe intermediate using carbonyl reductase coupled with glucose dehydrogenase

2020 ◽  
Author(s):  
Xiao‐Jian Zhang ◽  
Rong Zhou ◽  
Di Wu ◽  
Ya‐Qun Tang ◽  
Meng‐Ying Wang ◽  
...  
Keyword(s):  
Glucose Dehydrogenase ◽  
Carbonyl Reductase ◽  
Efficient Production

New insights into the stereospecific reduction by an (S) specific carbonyl reductase from Candida parapsilosis ATCC 7330: experimental and QM/MM studies

2020 ◽  
Vol 10 (17) ◽  
pp. 5925-5934 ◽  
Author(s):  
Sneha Sudhakara ◽  
Chandrasekaran Ramakrishnan ◽  
M. Michael Gromiha ◽  
Anju Chadha
Keyword(s):  
Quantum Mechanics ◽  
Molecular Mechanics ◽  
Reaction Mechanisms ◽  
Candida Parapsilosis ◽  
Carbonyl Reductase ◽  
Stereospecific Reduction ◽  
Candida Parapsilosis Atcc 7330 ◽  
Reduction Of Ketones

The quantum mechanics/molecular mechanics study of an (S) specific carbonyl reductase from C. parapsilosis ATCC 7330 showing a dual kinetic response for the reduction of ketones and α-ketoesters suggests different reaction mechanisms for the same.

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