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Erick Abreu Silveira - One of the best experts on this subject based on the ideXlab platform.
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modulation of the regioselectivity of thermomyces lanuginosus lipase via biocatalyst engineering for the ethanolysis of oil in fully anhydrous medium
BMC Biotechnology, 2017Co-Authors: Erick Abreu Silveira, Alessandra Basso, Simona Serban, Rita Pestana Mamede, Paulo W. Tardioli, Cristiane Sanchez Farinas, Sonia Morenoperez, Javier Rochamartin, Gloria FernandezlorenteAbstract:Enzymatic ethanolysis of oils (for example, high oleic sunflower oil containing 90% of oleic acid) may yield two different reaction products depending on the regioselectivity of the immobilized lipase biocatalyst. Some lipase biocatalysts exhibit a 1,3-regioselectivity and they produced 2 mols of fatty acid ethyl ester plus 1 mol of sn2-monoacylglycerol (2-MAG) per mol of triglyceride without the release of glycerol. Other lipase biocatalysts are completely non-regioselective releasing 3 mols of fatty acid ethyl ester and 1 mol of glycerol per mol of triglyceride. Lipase from Thermomyces lanuginosus (TLL) adsorbed on hydrophobic supports is a very interesting biocatalyst for the ethanolysis of oil. Modulation of TLL regioselectivity in anhydrous medium was intended via two strategies of TLL immobilization: a. - interfacial adsorption on different hydrophobic supports and b.- interfacial adsorption on a given hydrophobic support under different experimental conditions. Immobilization of TLL on supports containing divinylbenezene moieties yielded excellent 1,3-regioselective biocatalysts but immobilization of TLL on supports containing octadecyl groups yielded non-regioselective biocatalysts. On the other hand, TLL immobilized on Purolite C18 at pH 8.5 and 30 °C in the presence of traces of CTAB yielded a biocatalyst with a perfect 1,3-regioselectivity and a very interesting activity: 2.5 μmols of oil ethanolyzed per min per gram of immobilized derivative. This activity is 10-fold higher than the one of commercial Lipozyme TL IM. Immobilization of the same enzyme on the same support, but at pH 7.0 and 25 °C, led to a biocatalyst which can hydrolyze all ester bonds in TG backbone. Activity and regioselectivity of TLL in anhydrous media can be easily modulated via Biocatalysis Engineering producing very active immobilized derivatives able to catalyze the ethanolysis of triolein. When the biocatalyst was 1,3-regioselective a 33% of 2-monoolein was obtained and it may be a very interesting surfactant. When biocatalyst catalyzed the ethanolysis of the 3 positions during the reaction process, a 99% of ethyl oleate was obtained and it may be a very interesting drug-solvent and surfactant. The absence of acyl migrations under identical reaction conditions is clearly observed and hence the different activities and regioselectivities seem to be due to the different catalytic properties of different derivatives of TLL.
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Modulation of the regioselectivity of Thermomyces lanuginosus lipase via biocatalyst engineering for the Ethanolysis of oil in fully anhydrous medium
BMC, 2017Co-Authors: Erick Abreu Silveira, Sonia Moreno-perez, Alessandra Basso, Simona Serban, Rita Pestana Mamede, Paulo W. Tardioli, Cristiane Sanchez Farinas, Javier Rocha-martin, Gloria Fernandez-lorente, Jose M. GuisanAbstract:Abstract Background Enzymatic ethanolysis of oils (for example, high oleic sunflower oil containing 90% of oleic acid) may yield two different reaction products depending on the regioselectivity of the immobilized lipase biocatalyst. Some lipase biocatalysts exhibit a 1,3-regioselectivity and they produced 2 mols of fatty acid ethyl ester plus 1 mol of sn2-monoacylglycerol (2-MAG) per mol of triglyceride without the release of glycerol. Other lipase biocatalysts are completely non-regioselective releasing 3 mols of fatty acid ethyl ester and 1 mol of glycerol per mol of triglyceride. Lipase from Thermomyces lanuginosus (TLL) adsorbed on hydrophobic supports is a very interesting biocatalyst for the ethanolysis of oil. Modulation of TLL regioselectivity in anhydrous medium was intended via two strategies of TLL immobilization: a. - interfacial adsorption on different hydrophobic supports and b.- interfacial adsorption on a given hydrophobic support under different experimental conditions. Results Immobilization of TLL on supports containing divinylbenezene moieties yielded excellent 1,3-regioselective biocatalysts but immobilization of TLL on supports containing octadecyl groups yielded non-regioselective biocatalysts. On the other hand, TLL immobilized on Purolite C18 at pH 8.5 and 30 °C in the presence of traces of CTAB yielded a biocatalyst with a perfect 1,3-regioselectivity and a very interesting activity: 2.5 μmols of oil ethanolyzed per min per gram of immobilized derivative. This activity is 10-fold higher than the one of commercial Lipozyme TL IM. Immobilization of the same enzyme on the same support, but at pH 7.0 and 25 °C, led to a biocatalyst which can hydrolyze all ester bonds in TG backbone. Conclusions Activity and regioselectivity of TLL in anhydrous media can be easily modulated via Biocatalysis Engineering producing very active immobilized derivatives able to catalyze the ethanolysis of triolein. When the biocatalyst was 1,3-regioselective a 33% of 2-monoolein was obtained and it may be a very interesting surfactant. When biocatalyst catalyzed the ethanolysis of the 3 positions during the reaction process, a 99% of ethyl oleate was obtained and it may be a very interesting drug-solvent and surfactant. The absence of acyl migrations under identical reaction conditions is clearly observed and hence the different activities and regioselectivities seem to be due to the different catalytic properties of different derivatives of TLL
Uwe T Bornscheuer - One of the best experts on this subject based on the ideXlab platform.
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Biocatalysis enzymatic synthesis for industrial applications
Angewandte Chemie, 2021Co-Authors: Radka Snajdrova, Jeffrey C Moore, Kai Baldenius, Uwe T BornscheuerAbstract:Biocatalysis has found numerous applications in various fields as an alternative to chemical catalysis. The use of enzymes in organic synthesis, especially to make chiral compounds for pharmaceuticals as well for the flavors and fragrance industry, are the most prominent examples. In addition, biocatalysts are used on a large scale to make specialty and even bulk chemicals. This review intends to give illustrative examples in this field with a special focus on scalable chemical production using enzymes. It also discusses the opportunities and limitations of enzymatic syntheses using distinct examples and provides an outlook on emerging enzyme classes.
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Opportunities and challenges for combining chemo- and Biocatalysis
Nature Catalysis, 2018Co-Authors: Florian Rudroff, Harald Groger, Marko D Mihovilovic, Radka Snajdrova, Hans Iding, Uwe T BornscheuerAbstract:Chemical and biological catalysts provide distinct advantages and disadvantages to the synthetic chemist. This Review focuses on efforts to combine chemo- and biocatalysts, outlining the opportunities achievable by this approach and also efforts to overcome any incompatibilities between these different systems. The past decade has seen a substantial increase in successful examples of the combination of chemo- and Biocatalysis for multistep syntheses. This is driven by obvious advantages such as higher yields, decreased costs, environmental benefits and high selectivity. On the downside, efforts must be undertaken to combine the divergent reaction conditions, reagent tolerance and solvent systems of these ‘different worlds of catalysis’. Owing to progress in enzyme discovery and engineering, as well as in the development of milder and more compatible conditions for operating with various chemocatalysts, many historical limitations can already be overcome. This Review highlights the opportunities available in the chemical space of combined syntheses using prominent examples, but also discusses the current challenges and emerging solutions, keeping in mind the fast progress in transition metal-, organo-, photo-, electro-, hetero- and Biocatalysis.
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cascade catalysis strategies and challenges en route to preparative synthetic biology
Chemical Communications, 2015Co-Authors: Jan Muschiol, Uwe T Bornscheuer, Christin Peters, Nikolin Oberleitner, Marko D Mihovilovic, Florian RudroffAbstract:Nature's smartness and efficient assembling cascade type reactions inspired biologists and chemists all around the world. Tremendous effort has been directed towards the understanding and mimicking of such networks. In recent years considerable progress has been made in developing multistep one-pot reactions combining either advantage of chemo-, regio-, and stereoselectivity of biocatalysts or promiscuity and productivity of chemocatalysts. In this context several concepts, inspired by different disciplines (Biocatalysis, metabolic engineering, synthetic chemistry, and material science), have been evolved. This review will focus on major contributions in the field of cascade reactions over the last three years.
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microbial synthesis of medium chain α ω dicarboxylic acids and ω aminocarboxylic acids from renewable long chain fatty acids
Advanced Synthesis & Catalysis, 2014Co-Authors: Ji Won Song, Jung Hoo Lee, Uwe T Bornscheuer, Jin Byung ParkAbstract:Biotransformation of long-chain fatty acids into medium-chain α,ω-dicarboxylic acids or ω-aminocarboxylic acids could be achieved with biocatalysts. This study presents the production of α,ω-dicarboxylic acids (e.g., C9, C11, C12, C13) and ω-aminocarboxylic acids (e.g., C11, C12, C13) directly from fatty acids (e.g., oleic acid, ricinoleic acid, lesquerolic acid) using recombinant Escherichia coli-based biocatalysts. ω-Hydroxycarboxylic acids, which were produced from oxidative cleavage of fatty acids via enzymatic reactions involving a fatty acid double bond hydratase, an alcohol dehydrogenase, a Baeyer–Villiger monooxygenase and an esterase, were then oxidized to α,ω-dicarboxylic acids by alcohol dehydrogenase (ADH, AlkJ) from Pseudomonas putida GPo1 or converted into ω-aminocarboxylic acids by a serial combination of ADH from P. putida GPo1 and an ω-transaminase of Silicibacter pomeroyi. The double bonds present in the fatty acids such as ricinoleic acid and lesquerolic acid were reduced by E. coli-native enzymes during the biotransformations. This study demonstrates that the industrially relevant building blocks (C9 to C13 saturated α,ω-dicarboxylic acids and ω-aminocarboxylic acids) can be produced from renewable fatty acids using Biocatalysis.
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engineering the third wave of Biocatalysis
Nature, 2012Co-Authors: Uwe T Bornscheuer, Gjalt W Huisman, Romas J Kazlauskas, Stefan Lutz, Jeffrey C Moore, Karen RobinsAbstract:Over the past ten years, scientific and technological advances have established Biocatalysis as a practical and environmentally friendly alternative to traditional metallo- and organocatalysis in chemical synthesis, both in the laboratory and on an industrial scale. Key advances in DNA sequencing and gene synthesis are at the base of tremendous progress in tailoring biocatalysts by protein engineering and design, and the ability to reorganize enzymes into new biosynthetic pathways. To highlight these achievements, here we discuss applications of protein-engineered biocatalysts ranging from commodity chemicals to advanced pharmaceutical intermediates that use enzyme catalysis as a key step.
Zongbao K Zhao - One of the best experts on this subject based on the ideXlab platform.
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identification of usha as a major enzyme for nad degradation in escherichia coli
Enzyme and Microbial Technology, 2014Co-Authors: Lei Wang, Yongjin J Zhou, Xinping Lin, Yuxue Liu, Yixin Zhang, Wujun Liu, Zongbao K ZhaoAbstract:Nicotinamide adenine dinucleotide (NAD) and its reduced form NADH are essential cofactors for many redox biocatalysts. Because these cofactors are consumed in stoichiometric amounts, whole-cell biocatalysts have been routinely employed in order to reduce the costs. To further improve the efficacy of redox biocatalysts, it is essential to maintain the stability of nicotinamide cofactors, for which it is attractive to block degradation pathways for NAD(H). While the biosynthesis of NAD(H) has been well studied, it is less understood how NAD(H) are degraded. Here we demonstrated that UshA was a major periplasmic enzyme for NAD degradation in Escherichia coli. Purified recombinant UshA showed high pyrophosphatase activity with the catalytic efficiencies for hydrolysis of NAD and NADH at 3.7μM(-1)s(-1) and 1.4μM(-1)s(-1), respectively. Deletion of the ushA gene from the chromosome led to faster cell growth and improved extracellular NAD stability by 3-fold under conditions similar to whole-cell Biocatalysis. These results significantly enriched our understanding on NAD metabolism, and should facilitate many applications including designing more robust redox biocatalysts.
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engineering nad availability for escherichia coli whole cell Biocatalysis a case study for dihydroxyacetone production
Microbial Cell Factories, 2013Co-Authors: Lei Wang, Yongjin J Zhou, Wei Yang, Zhiwei Zhu, Sufang Zhang, Zongbao K ZhaoAbstract:Background: Whole-cell redox Biocatalysis has been intensively explored for the production of valuable compounds because excellent selectivity is routinely achieved. Although the cellular cofactor level, redox state and the corresponding enzymatic activity are expected to have major effects on the performance of the biocatalysts, our ability remains limited to predict the outcome upon variation of those factors as well as the relationship among them. Results: In order to investigate the effects of cofactor availability on whole-cell redox Biocatalysis, we devised recombinant Escherichia coli strains for the production of dihydroxyacetone (DHA) catalyzed by the NAD + -dependent glycerol dehydrogenase (GldA). In this model system, a water-forming NAD + oxidase (NOX) and a NAD + transporter (NTT4) were also co-expressed for cofactor regeneration and extracellular NAD + uptake, respectively. We found that cellular cofactor level, NAD + /NADH ratio and NOX activity were not only straindependent, but also growth condition-dependent, leading to significant differences in specific DHA titer among different whole-cell biocatalysts. The host E. coli DH5α had the highest DHA specific titer of 0.81 g/gDCW with the highest NAD + /NADH ratio of 6.7 and NOX activity of 3900 U. The biocatalyst had a higher activity when induced with IPTG at 37°C for 8 h compared with those at 30°C for 8 h and 18 h. When cells were transformed with the ntt4 gene, feeding NAD + during the cell culture stage increased cellular NAD(H) level by 1.44 fold and DHA specific titer by 1.58 fold to 2.13 g/gDCW. Supplementing NAD + during the biotransformation stage was also beneficial to cellular NAD(H) level and DHA production, and the highest DHA productivity reached 0.76 g/gDCW/h. Cellular NAD(H) level, NAD + /NADH ratio, and NOX and GldA activity dropped over time during the biotransformation process. Conclusions: High NAD + /NADH ratio driving by NOX was very important for DHA production. Once cofactor was efficiently cycled, high cellular NAD(H) level was also beneficial for whole-cell redox Biocatalysis. Our results indicated that NAD + transporter could be applied to manipulate redox cofactor level for Biocatalysis. Moreover, we
Martin Hartmann - One of the best experts on this subject based on the ideXlab platform.
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Recent Progress in Biocatalysis with Enzymes Immobilized on Mesoporous Hosts
Topics in Catalysis, 2012Co-Authors: Zhou Zhou, Martin HartmannAbstract:Enzymes are highly desirable in green and sustainable chemistry. One of the major issues in Biocatalysis is enzyme stabilization under in vitro process conditions and catalyst recycling. In recent years, mesoporous materials have been extensively explored as supports for immobilization of enzymes. This review describes the recent developments in enzyme immobilization in mesoporous materials and their potential applications as biocatalysts in the chemical and pharmaceutical industry.
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Biocatalysis with enzymes immobilized on mesoporous hosts the status quo and future trends
Journal of Materials Chemistry, 2010Co-Authors: Martin Hartmann, Dirk JungAbstract:Biocatalysis opens the door to green and sustainable processes in synthetic chemistry, in the production of natural products, and in waste management. Furthermore, due to the often similar reaction conditions, Biocatalysis is ideally suited for realization of multi-step reactions. The key to successful process optimization, especially for industrial applications of enzyme-catalyzed reactions, is immobilization. Enzyme immobilization on ordered mesoporous supports enhances their operational stability and enables the use of enzymes as reusable and robust biocatalysts even for continuous processes. In this feature article, the use of enzymes immobilized on mesoporous supports in Biocatalysis is reviewed and future trends are pointed out.
Gloria Fernandezlorente - One of the best experts on this subject based on the ideXlab platform.
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modulation of the regioselectivity of thermomyces lanuginosus lipase via biocatalyst engineering for the ethanolysis of oil in fully anhydrous medium
BMC Biotechnology, 2017Co-Authors: Erick Abreu Silveira, Alessandra Basso, Simona Serban, Rita Pestana Mamede, Paulo W. Tardioli, Cristiane Sanchez Farinas, Sonia Morenoperez, Javier Rochamartin, Gloria FernandezlorenteAbstract:Enzymatic ethanolysis of oils (for example, high oleic sunflower oil containing 90% of oleic acid) may yield two different reaction products depending on the regioselectivity of the immobilized lipase biocatalyst. Some lipase biocatalysts exhibit a 1,3-regioselectivity and they produced 2 mols of fatty acid ethyl ester plus 1 mol of sn2-monoacylglycerol (2-MAG) per mol of triglyceride without the release of glycerol. Other lipase biocatalysts are completely non-regioselective releasing 3 mols of fatty acid ethyl ester and 1 mol of glycerol per mol of triglyceride. Lipase from Thermomyces lanuginosus (TLL) adsorbed on hydrophobic supports is a very interesting biocatalyst for the ethanolysis of oil. Modulation of TLL regioselectivity in anhydrous medium was intended via two strategies of TLL immobilization: a. - interfacial adsorption on different hydrophobic supports and b.- interfacial adsorption on a given hydrophobic support under different experimental conditions. Immobilization of TLL on supports containing divinylbenezene moieties yielded excellent 1,3-regioselective biocatalysts but immobilization of TLL on supports containing octadecyl groups yielded non-regioselective biocatalysts. On the other hand, TLL immobilized on Purolite C18 at pH 8.5 and 30 °C in the presence of traces of CTAB yielded a biocatalyst with a perfect 1,3-regioselectivity and a very interesting activity: 2.5 μmols of oil ethanolyzed per min per gram of immobilized derivative. This activity is 10-fold higher than the one of commercial Lipozyme TL IM. Immobilization of the same enzyme on the same support, but at pH 7.0 and 25 °C, led to a biocatalyst which can hydrolyze all ester bonds in TG backbone. Activity and regioselectivity of TLL in anhydrous media can be easily modulated via Biocatalysis Engineering producing very active immobilized derivatives able to catalyze the ethanolysis of triolein. When the biocatalyst was 1,3-regioselective a 33% of 2-monoolein was obtained and it may be a very interesting surfactant. When biocatalyst catalyzed the ethanolysis of the 3 positions during the reaction process, a 99% of ethyl oleate was obtained and it may be a very interesting drug-solvent and surfactant. The absence of acyl migrations under identical reaction conditions is clearly observed and hence the different activities and regioselectivities seem to be due to the different catalytic properties of different derivatives of TLL.