scholarly journals Yeast-Mediated Stereoselective Reduction of α-Acetylbutyrolactone

2018 ◽  
Vol 8 (8) ◽  
pp. 1334 ◽  
Author(s):  
Wanda Mączka ◽  
Katarzyna Wińska ◽  
Małgorzata Grabarczyk ◽  
Barbara Żarowska
Keyword(s):  
Organic Solvent ◽  
Yarrowia Lipolytica ◽  
Enantiomeric Excess ◽  
Deep Eutectic Solvent ◽  
Ester Group ◽  
Resting Cells ◽  
Media Composition ◽  
Yeast Strains ◽  
Optically Pure ◽  
Diastereomeric Excess

α’-1’-Hydroxyethyl-γ-butyrolactone—a product of reduction of α-acetylbutyrolactone possesses two stereogenic centres and two reactive functionalities (an alcohol and an ester group). Additionally, this compound has a similar structure to γ-butyrolactone (GBL) which is psychoactive. In the present work, biotransformation using seven yeast strains was used to obtain anti stereoisomers of α’-1’-hydroxyethyl-γ-butyrolactone. The process was carried out in both growing and resting culture. The effect of media composition and organic solvent addition on stereoselectivity and effectiveness of biotransformation was also studied. After one day of transformation, optically pure (3R,1’R)-hydroxylactone was obtained by means of Yarrowia lipolytica P26A in YPG medium (yeast extract (1%), peptone (2%) and glucose (2%)). In turn, the use of resting cells culture of Candida viswanathi AM120 in the presence of 10% DES (deep eutectic solvent) allowed us to obtain a (3S,1’S)-enantiomer with de = 85% (diastereomeric excess) and ee 76% (enantiomeric excess).

scholarly journals Efficient Biocatalytic Preparation of Optically Pure (R)-1-[4-(Trifluoromethyl)phenyl]ethanol by Recombinant Whole-Cell-Mediated Reduction

Catalysts ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 391 ◽  
Author(s):  
Ying Chen ◽  
Nana Xia ◽  
Yuewang Liu ◽  
Pu Wang
Keyword(s):  
Organic Solvent ◽  
Asymmetric Reduction ◽  
Enantiomeric Excess ◽  
Aqueous System ◽  
Cell Membrane Permeability ◽  
Buffer Solution ◽  
Preparative Scale ◽  
Buffer Medium ◽  
Polar Organic Solvent ◽  
Optically Pure

(R)-1-[4-(Trifluoromethyl)phenyl]ethanol is an important pharmaceutical intermediate of a chemokine CCR5 antagonist. In the present study, a bioprocess for the asymmetric reduction of 4-(trifluoromethyl)acetophenone to (R)-1-[4-(trifluoromethyl)phenyl]ethanol was developed by recombinant Escherichia coli cells with excellent enantioselectivity. In order to overcome the conversion limitation performed in the conventional buffer medium resulting from poor solubility of non-natural substrate, we subsequently established a polar organic solvent-aqueous medium to improve the efficacy. Isopropanol was selected as the most suitable cosolvent candidate, based on the investigation on a substrate solubility test and cell membrane permeability assay in different organic solvent-buffer media. Under the optimum conditions, the preparative-scale asymmetric reduction generated a 99.1% yield with >99.9% product enantiomeric excess (ee) in a 15% (v/v) isopropanol proportion, at 100 mM of 4-(trifluoromethyl)acetophenone within 3 h. Compared to bioconversion in the buffer medium, the developed isopropanol-aqueous system enhanced the substrate concentration by 2-fold with a remarkably improved yield (from 62.5% to 99.1%), and shortened the reaction time by 21 h. Our study gave the first example for a highly enantioselective production of (R)-1-[4-(trifluoromethyl)phenyl]ethanol by a biological method, and the bioreduction of 4-(trifluoromethyl)acetophenone in a polar organic solvent-aqueous system was more efficient than that in the buffer solution only. This process is also scalable and has potential in application.

scholarly journals Bienzymatic Cascade for the Synthesis of an Optically Active O-benzoyl Cyanohydrin

Catalysts ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 522 ◽  
Author(s):  
Laura Leemans ◽  
Luuk van Langen ◽  
Frank Hollmann ◽  
Anett Schallmey
Keyword(s):  
Organic Solvent ◽  
Manihot Esculenta ◽  
Direct Synthesis ◽  
Enantiomeric Excess ◽  
Candida Antarctica ◽  
Optically Active ◽  
Candida Antarctica Lipase ◽  
Hydroxynitrile Lyase ◽  
Lipase A ◽  
Optically Pure

A concurrent bienzymatic cascade for the synthesis of optically pure (S)-4-methoxymandelonitrile benzoate ((S)-3) starting from 4-anisaldehyde (1) has been developed. The cascade involves an enantioselective Manihot esculenta hydroxynitrile lyase-catalyzed hydrocyanation of 1, and the subsequent benzoylation of the resulting cyanohydrin (S)-2 catalyzed by Candida antarctica lipase A in organic solvent. To accomplish this new direct synthesis of the protected enantiopure cyanohydrin, both enzymes were immobilized and each biocatalytic step was studied separately in search for a window of compatibility. In addition, potential cross-interactions between the two reactions were identified. Optimization of the cascade resulted in 81% conversion of the aldehyde to the corresponding benzoyl cyanohydrin with 98% enantiomeric excess.

scholarly journals ω-Amino Acid:Pyruvate Transaminase from Alcaligenes denitrificans Y2k-2: a New Catalyst for Kinetic Resolution of β-Amino Acids and Amines

2004 ◽  
Vol 70 (4) ◽  
pp. 2529-2534 ◽  
Author(s):  
Hyungdon Yun ◽  
Seongyop Lim ◽  
Byung-Kwan Cho ◽  
Byung-Gee Kim
Keyword(s):  
Amino Acids ◽  
Kinetic Resolution ◽  
Specific Activity ◽  
Expression System ◽  
Enantiomeric Excess ◽  
Selective Enrichment ◽  
Alcaligenes Denitrificans ◽  
Keto Acids ◽  
Optically Pure ◽  
High Stereoselectivity

ABSTRACT Alcaligenes denitrificans Y2k-2 was obtained by selective enrichment followed by screening from soil samples, which showed ω-amino acid:pyruvate transaminase activity, to kinetically resolve aliphatic β-amino acid, and the corresponding structural gene (aptA) was cloned. The gene was functionally expressed in Escherichia coli BL21 by using an isopropyl-β-d-thiogalactopyranoside (IPTG)-inducible pET expression system (9.6 U/mg), and the recombinant AptA was purified to show a specific activity of 77.2 U/mg for l-β-amino-n-butyric acid (l-β-ABA). The enzyme converts various β-amino acids and amines to the corresponding β-keto acids and ketones by using pyruvate as an amine acceptor. The apparent Km and V max for l-β-ABA were 56 mM and 500 U/mg, respectively, in the presence of 10 mM pyruvate. In the presence of 10 mM l-β-ABA, the apparent Km and V max for pyruvate were 11 mM and 370 U/mg, respectively. The enzyme exhibits high stereoselectivity (E > 80) in the kinetic resolution of 50 mM d,l-β-ABA, producing optically pure d-β-ABA (99% enantiomeric excess) with 53% conversion.

Characterization of major protein phosphatases from selected species of Kluyveromyces. Comparison with protein phosphatases from Yarrowia lipolytica

2001 ◽  
Vol 47 (9) ◽  
pp. 861-870 ◽  
Author(s):  
Pascale Jolivet ◽  
Edith Bergeron ◽  
Haguith Benyair ◽  
Jean-Claude Meunier
Keyword(s):  
Acid Phosphatase ◽  
Yarrowia Lipolytica ◽  
Protein Phosphatase ◽  
Protein Phosphatases ◽  
Major Protein ◽  
Ethanol Treatment ◽  
Early Stationary Phase ◽  
Yeast Strains ◽  
Deficient Medium

Casein phosphatase activities have been identified in five yeast strains grown on Pi-deficient medium. Maximal endocellular activities appeared in the exponential phase. Exocellular phosphatases were significantly produced from Yarrowia lipolytica W-29 and Kluyveromyces marxianus, in the early stationary phase. Major phosphatases from K. marxianus were one heavy acid phosphatase composed of 64–67 kDa subunits, which could be secreted in the medium, and one type 2A protein phosphatase with an apparent molecular mass of 147 kDa and a 52 kDa catalytic subunit dissociated by 80% ethanol treatment. The characteristics of phosphatases purified from K. marxianus were compared with those previously purified from Y. lipolytica.Key words: yeast, type 2A protein phosphatase, acid phosphatase, [32P]casein, Pi deficiency.

scholarly journals Bioreactor Co-Cultivation of High Lipid and Carotenoid Producing Yeast Rhodotorula kratochvilovae and Several Microalgae under Stress

2021 ◽  
Vol 9 (6) ◽  
pp. 1160
Author(s):  
Martin Szotkowski ◽  
Jiří Holub ◽  
Samuel Šimanský ◽  
Klára Hubačová ◽  
Pavlína Sikorová ◽  
...  
Keyword(s):  
Positive Impact ◽  
Small Scale ◽  
Biomass Growth ◽  
Media Composition ◽  
Yeast Strains ◽  
High Lipid ◽  
Algae Growth ◽  
Chlorophyll Production ◽  
Lipid Metabolites ◽  
Present Pilot Study

The co-cultivation of red yeasts and microalgae works with the idea of the natural transport of gases. The microalgae produce oxygen, which stimulates yeast growth, while CO2 produced by yeast is beneficial for algae growth. Both microorganisms can then produce lipids. The present pilot study aimed to evaluate the ability of selected microalgae and carotenogenic yeast strains to grow and metabolize in co-culture. The effect of media composition on growth and metabolic activity of red yeast strains was assessed simultaneously with microalgae mixotrophy. Cultivation was transferred from small-scale co-cultivation in Erlenmeyer flasks to aerated bottles with different inoculation ratios and, finally, to a 3L bioreactor. Among red yeasts, the strain R. kratochvilovae CCY 20-2-26 was selected because of the highest biomass production on BBM medium. Glycerol is a more suitable carbon source in the BBM medium and urea was proposed as a compromise. From the tested microalgae, Desmodesmus sp. were found as the most suitable for co-cultivations with R. kratochvilovae. In all co-cultures, linear biomass growth was found (144 h), and the yield was in the range of 8.78–11.12 g/L of dry biomass. Lipids increased to a final value of 29.62–31.61%. The FA profile was quite stable with the UFA portion at about 80%. Around 1.98–2.49 mg/g CDW of carotenoids with torularhodine as the major pigment were produced, ubiquinone production reached 5.41–6.09 mg/g, and ergosterol yield was 6.69 mg/g. Chlorophyll production was very low at 2.11 mg/g. Pilot experiments have confirmed that carotenogenic yeasts and microalgae are capable of symbiotic co-existence with a positive impact om biomass growth and lipid metabolites yields.

scholarly journals Calcium(II)-mediated resolution of methyl o-chloromandelate with chiral O,O′-dibenzoyltartaric acid in preparative scale

2019 ◽  
Vol 42 (1) ◽  
pp. 19-22
Author(s):  
Hong-Wu Xu ◽  
Li-Huan Wu ◽  
Qiang Ren ◽  
Cui-Yu Liu ◽  
Guan-Qing Yan
Keyword(s):  
Mother Liquor ◽  
Enantiomeric Excess ◽  
Ethanol Solution ◽  
Preparative Scale ◽  
Mixed Ligands ◽  
Excess Value ◽  
Optically Pure

Abstract We report here the coordination-mediated resolution of methyl o-chloromandelate, which is a key intermediate for clopidogrel, in preparative scale. The reaction of CaO, optically pure (2R, 3R)-O,O′-dibenzoyltartaric acid, and methyl o-chloromandelate in ethanol solution afforded a mixed-ligands calcium(II) complex that was further purified by stirring of the crystals in hot methanol. Methyl (R)-o-chloromandelate was obtained in good enantiomeric excess value (>99.5%) and yield (71%) by treatment of the complex with acid. At the same time, (2R, 3R)-O,O′-dibenzoyltartaric acid was recovered in 72% yield. In addition, methyl (S)-o-chloromandelate was obtained in good enantiomeric excess value (>99.5%) and yield (73%) by recovery from the mother liquor and resolution with the same procedure for methyl (R)-o-chloromandelate, except that (2S, 3S)-O,O′-dibenzoyltartaric acid was used as the resolving reagent.

scholarly journals Stereoselective Esterase from Pseudomonas putida IFO12996 Reveals α/β Hydrolase Folds for d-β-Acetylthioisobutyric Acid Synthesis

2005 ◽  
Vol 187 (24) ◽  
pp. 8470-8476 ◽  
Author(s):  
Fatemeh Elmi ◽  
Hsin-Tai Lee ◽  
Jen-Yeng Huang ◽  
Yin-Cheng Hsieh ◽  
Yu-Ling Wang ◽  
...  
Keyword(s):  
Pseudomonas Putida ◽  
Enzyme Inhibitors ◽  
Specific Activity ◽  
Methyl Esters ◽  
Enantiomeric Excess ◽  
Angiotensin Converting Enzyme Inhibitors ◽  
Acid Synthesis ◽  
Ester Group ◽  
Catalytic Triad ◽  
Converting Enzyme Inhibitors

ABSTRACT Esterase (EST) from Pseudomonas putida IFO12996 catalyzes the stereoselective hydrolysis of methyl dl-β-acetylthioisobutyrate (dl-MATI) to produce d-β-acetylthioisobutyric acid (DAT), serving as a key intermediate for the synthesis of angiotensin-converting enzyme inhibitors. The EST gene was cloned and expressed in Escherichia coli; the recombinant protein is a non-disulfide-linked homotrimer with a monomer molecular weight of 33,000 in both solution and crystalline states, indicating that these ESTs function as trimers. EST hydrolyzed dl-MATI to produce DAT with a degree of conversion of 49.5% and an enantiomeric excess value of 97.2% at an optimum pH of about 8 to 10 and an optimum temperature of about 57 to 67°C. The crystal structure of EST has been determined by X-ray diffraction to a resolution of 1.6 Å, confirming that EST is a member of the α/β hydrolase fold superfamily of enzymes and includes a catalytic triad of Ser97, Asp227, and His256. The active site is located approximately in the middle of the molecule at the end of a pocket ∼12 Å deep. EST can hydrolyze the methyl ester group without affecting the acetylthiol ester moiety in dl-MATI. The examination of substrate specificity of EST toward other linear esters revealed that the enzyme showed specific activity toward methyl esters and that it recognized the configuration at C-2.

Practical Early Development Synthesis of Nav1.7 Inhibitor GDC-0310

Synthesis ◽  
2020 ◽  
Vol 52 (22) ◽  
pp. 3406-3414 ◽  
Author(s):  
Andreas Stumpf ◽  
Frédéric St-Jean ◽  
David Lao ◽  
Zhigang Ken Cheng ◽  
Remy Angelaud ◽  
...  
Keyword(s):  
Methyl Ester ◽  
Early Development ◽  
Enantiomeric Excess ◽  
Coupling Reaction ◽  
Active Pharmaceutical Ingredient ◽  
Ester Group ◽  
Cross Coupling Reaction ◽  
Palladium Catalyzed ◽  
Aromatic Bromination ◽  
Displacement Approach

The concise early development route to the Nav1.7 inhibitor GDC-0310 is described. The active pharmaceutical ingredient (API) contains one stereocenter, which was obtained with high enantiomeric excess (>99:1) by using an SN2 displacement approach to connect two intermediates: a chiral benzyl alcohol and a piperidine. The synthesis of the piperidine building block proceeded via a regioselective SNAr reaction on 1-chloro-2,4-difluorobenzene by N-Boc-4-piperidinemethanol, followed by installation of the methyl ester group by electrophilic aromatic bromination and a palladium-catalyzed alkoxycarbonylation. A subsequent Suzuki–Miyaura cross-coupling reaction was then telescoped directly into cleavage of the Boc group to provide the advanced piperidine intermediate. The key feature of the synthesis is the highly selective SN2 displacement of the chiral mesylate of (R)-1-(3,5-dichlorophenyl)ethan-1-ol with the piperidine intermediate, followed by a chiral purity upgrade via the corresponding (1S)-(+)-camphorsulfonic acid salt. After standard hydrolysis of the methyl ester and CDI mediated amidation to couple the resulting acid with methanesulfonamide, enantiomerically pure GDC-0310 was obtained in high overall yield (37%) on a 6.5 kilogram scale.

Isolation of an esterase-producing Trichosporon brassicae and its catalytic performance in kinetic resolution of ketoprofen

2001 ◽  
Vol 47 (12) ◽  
pp. 1101-1106 ◽  
Author(s):  
Duan Shen ◽  
Jian-He Xu ◽  
Peng-Fei Gong ◽  
Hui-Yuan Wu ◽  
You-Yan Liu
Keyword(s):  
Ethyl Ester ◽  
Sole Carbon Source ◽  
Kinetic Resolution ◽  
Enantiomeric Excess ◽  
Catalytic Performance ◽  
Soil Samples ◽  
Enantioselective Hydrolysis ◽  
Resting Cells ◽  
Enantiomeric Ratio ◽  
Hydrolysis Of

A yeast strain CGMCC 0574, identified as Trichosporon brassicae, was selected from 92 strains for its high (S) selectivity in the hydrolysis of ketoprofen ethyl ester. The effective strains of the microorganisms were isolated from soil samples with the ester as the sole carbon source. The ethyl ester proved to be the best substrate for resolution of ketoprofen among several ketoprofen esters examined. The resting cells of CGMCC 0574 could catalyze the hydrolysis of ketoprofen ethyl ester with an enantiomeric ratio of 44.9, giving (S)-ketoprofen an enantiomeric excess of 91.5% at 42% conversion.Key words: ketoprofen, biocatalytic resolution, enantioselective hydrolysis, microbial esterase, Trichosporon brassicae.

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