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biocatalysis and enzyme

Yang Woo Lee, Passarut Boonmongkolras, Eun Jin Son, Jinhyun Kim, Sahng Ha Lee, Su Keun Kuk, Jong Wan Ko, Byungha Shin, Chan Beum Park
Redox enzymes catalyze fascinating chemical reactions with excellent regio- and stereo-specificity. Nicotinamide adenine dinucleotide cofactor is essential in numerous redox biocatalytic reactions and needs to be regenerated because it is consumed as an equivalent during the enzymatic turnover. Here we report on unbiased photoelectrochemical tandem assembly of a photoanode (FeOOH/BiVO4 ) and a perovskite photovoltaic to provide sufficient potential for cofactor-dependent biocatalytic reactions. We obtain a high faradaic efficiency of 96...
October 11, 2018: Nature Communications
Ana M L Sousa, Tai-De Li, Sabu Varghese, Peter James Halling, King Hang Aaron Lau
Proteins represent complex biomolecules capable of wide-ranging but also highly specific functionalities. Their immobilization on material supports can enable broad applications from sensing, industrial biocatalysis, to biomedical interfaces and materials. We demonstrate the advantages of using aqueous-processed crosslinked polyphenol coatings for immobilizing proteins, including IgG, avidin, and various single and multi-domain enzymes on diverse materials, to enable active biofunctional structures (e.g. ca...
October 9, 2018: ACS Applied Materials & Interfaces
Ma Ángeles Cabrera, Jenny M Blamey
To date, many industrial processes are performed using chemical compounds, which are harmful to nature. An alternative to overcome this problem is biocatalysis, which uses whole cells or enzymes to carry out chemical reactions in an environmentally friendly manner. Enzymes can be used as biocatalyst in food and feed, pharmaceutical, textile, detergent and beverage industries, among others. Since industrial processes require harsh reaction conditions to be performed, these enzymes must possess several characteristics that make them suitable for this purpose...
October 5, 2018: Biological Research
Meena Bisht, Dibyendu Mondal, Matheus M Pereira, Mara G Freire, P Venkatesu, J A P Coutinho
There is a considerable interest in the use of structurally stable and catalytically active enzymes, such as cytochrome C (Cyt C), in the pharmaceutical and fine chemical industries. However, harsh process conditions, such as temperature, pH, and presence of organic solvents, are the major barriers to the effective use of enzymes in biocatalysis. Herein, we demonstrate the suitability of bio-based ionic liquids (ILs) formed by the cholinium cation and dicarboxylate-based anions as potential media for enzymes, in which remarkable enhanced activity and improved stability of Cyt C against multiple stresses were obtained...
October 21, 2017: Green Chemistry: An International Journal and Green Chemistry Resource: GC
Yuji Nakano, Kyle F Biegasiewicz, Todd K Hyster
Initiating and terminating free-radical reactionis via hydrogen atom transfer (HAT) is an attractive means of avoiding substrate prefunctionalization. Small molecule catalysts and reagents, however, struggle to execute this fundamental step with useful levels of diastereoselectivity and enantioselectivity. In contrast, nature often carries out HAT with exquisite levels of selectivity for even electronically unactivated carbon-hydrogen bonds. By understanding how enzymes exploit and control this fundamental step, new strategies can be developed to address several long-standing challenges in free-radical reactions...
September 27, 2018: Current Opinion in Chemical Biology
C M Romero, F C Spuches, A H Morales, N I Perotti, M C Navarro, M I Gómez
Lipases (EC are very used industrial enzymes but presents drawbacks such as lack of stability, and poor recyclability. Most of these obstacles can be solved by lipase immobilization. The objective of this work was evaluated to magnetic magnesium spinel nanoparticles as support for lipase immobilization by covalent bound. The techniques used for nanoparticles synthesis presented advantages in the size selection of the nanoparticles obtained (60-100 nm). The immobilization of Candida rugosa lipase (CRL) was optimized...
September 15, 2018: Colloids and Surfaces. B, Biointerfaces
Santiago N Chanquia, Erika Ripani, Alicia Baldessari, Guadalupe García Liñares
In this work we present an efficient, environmentally friendly approach to the synthesis of a series of hyodeoxycholic acid derivatives applying Biocatalysis. Fifteen acetyl and ester derivatives, twelve of them new, were obtained through an enzymatic strategy in a fully regioselective way and in very good to excellent yield. In order to find the optimal reaction conditions, the influence of several parameters such as enzyme source, alcohol or acylating agent:substrate ratio, enzyme:substrate ratio, temperature and reaction solvent was considered...
September 12, 2018: Steroids
Stefan Velikogne, Verena Resch, Carina Dertnig, Joerg H Schrittwieser, Wolfgang Kroutil
Imine reductases (IREDs) have recently become a primary focus of research in biocatalysis, complementing other classes of amine-forming enzymes such as transaminases and amine dehydrogenases. Following in the footsteps of other research groups, we have established a set of IRED biocatalysts by sequence-based in silico enzyme discovery. In this study, we present basic characterisation data for these novel IREDs and explore their activity and stereoselectivity using a panel of structurally diverse cyclic imines as substrates...
August 13, 2018: ChemCatChem
Friso S Aalbers, Marco W Fraaije
One approach to bringing enzymes together for multienzyme biocatalysis is genetic fusion. This enables the production of multifunctional enzymes that can be used for whole-cell biotransformations or for in vitro (cascade) reactions. In some cases and in some aspects, such as expression and conversions, the fused enzymes outperform a combination of the individual enzymes. In contrast, some enzyme fusions are greatly compromised in activity and/or expression. In this Minireview, we give an overview of studies on fusions between two or more enzymes that were used for biocatalytic applications, with a focus on oxidative enzymes...
September 4, 2018: Chembiochem: a European Journal of Chemical Biology
Ekaterina Yu Bezsudnova, Tatiana N Stekhanova, Anna V Popinako, Tatiana V Rakitina, Alena Yu Nikolaeva, Konstantin M Boyko, Vladimir O Popov
Substrate and reaction promiscuity is a remarkable property of some enzymes and facilitates the adaptation to new metabolic demands in the evolutionary process. Substrate promiscuity is also a basis for protein engineering for biocatalysis. However, molecular principles of enzyme promiscuity are not well understood. Even for the widely studied PLP-dependent transaminases of class III, the reliable prediction of the biocatalytically important amine transaminase activity is still difficult if the desired activity is unrelated to the natural activity...
September 3, 2018: Applied Microbiology and Biotechnology
Pallvi Sehajpal, Seema Kirar, Saptarshi Ghosh, Uttam Chand Banerjee
Biocatalysis has shown tremendous potential in the synthesis of drugs and drug intermediates in the last decade. Screening of novel biocatalysts from the natural genome space is the growing trend to replenish the harsh chemical synthetic routes, commonly used in the pharmaceutical and chemical industry. Here, we report a novel ketoreductase (KERD) and a nitrile reductase isolated from the PCR based library generated from the genome of Rhodococcus ruber and Bacillus subtilis, respectively. Both the proteins are hypothetical in nature as there is no putative homology found in the database, although both the enzymes have significant activity towards the synthesis of chiral alcohols and amines...
November 2018: Enzyme and Microbial Technology
Zhiyong Sun, Ulrich Glebe, Himanshu Charan, Alexander Böker, Changzhu Wu
Despite the rapid development of Pickering interfacial catalysis (PIC) at liquid-liquid interfaces with chemocatalysts, the use of unstable biocatalysts at emulsion interfaces remains a technical challenge. Herein, we present a Pickering interfacial biocatalysis (PIB) platform based on robust and recyclable enzyme-polymer conjugates that act as both catalytic sites and stabilizers at the interface of Pickering emulsions. The conjugates were prepared by growing poly(N-isopropylacrylamide) on a fragile enzyme, benzaldehyde lyase, under physiological conditions...
October 15, 2018: Angewandte Chemie
Galong Li, Pei Ma, Yuan He, Yifan Zhang, Yane Luo, Ce Zhang, Haiming Fan
The laccase-Cu2 O-nanowire mesocrystal hybrid materials were developed with a superior catalytic activity inspired by natural biocatalysis processes in living cells that highly resemble the metal ions activation and the well-organized spatial structure of the natural rough endoplasmic reticulum. The enzyme and nanobiocatalyst activities of the obtained hybrid material exhibited an approximate 10-fold and 2.2-fold increase than the free enzyme, surpassing the currently available nanobiocatalysts. The comprehensive catalytic performance of the hybrid materials has been further demonstrated using a prototype continuous-flow reactor for the bioremediation of 2,4-dichlorophenol-contaminated water, which showed a high degradation efficiency and remarkable reusability...
August 27, 2018: Nano Letters
Soňa Hermanová, Daniel Bouša, Vlastimil Mazánek, David Sedmidubský, Jan Plutnar, Martin Pumera, Zdenek Sofer
The application of enzymes is a crucial issue for current biotechnological application in pharmaceutical as well as food and cosmetic industry. Effective platforms for enzyme immobilization are necessary for their industrial use in various biosynthesis procedures. Such platforms must provide high yield of immobilization as well as retain high activity at various conditions for their large scale applications. Graphene derivatives like hydrogenated graphene (graphane) and fluorographene can be applied for enzyme immobilization with close to 100% yield and activities of the composites significantly exceeding activity of free enzymes...
August 16, 2018: Chemistry: a European Journal
Nadia Guajardo, Pablo Domínguez de María
Deep eutectic solvents (DES) may become important alternatives as versatile, biodegradable, and cost-effective solvents for biocatalysis. Especially for reactions where substrates and products of different polarities are combined, the design of a tailored solvent that may dissolve all compounds-while being enzyme-compatible at the same time-appears to be a strong ally in sustainable chemistry. Herein it is shown that the combination of DES with "water as cosolvent" (in a range from 5% to 20% water, v/v) leads to non-conventional solvents with significantly reduced viscosity...
2018: Methods in Molecular Biology
Fu-Xing Niu, Xin He, Ya-Qin Wu, Jian-Zhong Liu
α-Pinene is a natural and active monoterpene, which is widely used as a flavoring agent and in fragrances, pharmaceuticals, and biofuels. Although it has been successfully produced by genetically engineered microorganisms, the production level of pinene is much lower than that of hemiterpene (isoprene) and sesquiterpenes (farnesene) to date. We first improved pinene tolerance to 2.0% and pinene production by adaptive laboratory evolution after atmospheric and room temperature plasma (ARTP) mutagenesis and overexpression of the efflux pump to obtain the pinene tolerant strain Escherichia coli YZFP, which is resistant to fosmidomycin...
2018: Frontiers in Microbiology
Shu-Ping Zou, Xiu-Ling Xuan, Zhi-Jian Wang, Yu-Guo Zheng
Epoxide hydrolase-mediated biocatalysis has a great prospective in the biosynthesis of optically pure epoxides. The present work targets toward the thermo-stabilization of epoxide hydrolase by covalent conjugation with polysaccharide. An epoxide hydrolase from Agrobacterium radiobacter (ArEH) was modified by covalent coupling to seven oxidized polysaccharides with different chemical structures and characteristics. Among all conjugates, ArEH with ficoll exhibited both the highest specific activity (494 U/mg) and half-life at 60 °C (t1/2  = 183 min)...
November 2018: International Journal of Biological Macromolecules
Juan M Bolivar, Donya Valikhani, Bernd Nidetzky
Continuous (flow) reactors have drawn a wave of renewed interest in biocatalysis. Many studies find that the flow reactor offers enhanced conversion efficiency. What the reported reaction intensification actually consists in, however, often remains obscure. Here, a canonical microreactor design for heterogeneously catalyzed continuous biotransformations, featuring flow microchannels that contain the enzyme immobilized on their wall surface are examined. Glycosylations by sucrose phosphorylase are used to assess the potential for reaction intensification due to microscale effects...
August 9, 2018: Biotechnology Journal
Sarah Schmidt-Dannert, Guoqiang Zhang, Timothy Johnston, Maureen B Quin, Claudia Schmidt-Dannert
Biological materials that are genetically encoded and can self-assemble offer great potential as immobilization platforms in industrial biocatalysis. Protein-based scaffolds can be used for the spatial organization of enzymes, to stabilize the catalysts and provide optimal microenvironments for reaction sequences. In our previous work, we created a protein scaffold for enzyme localization by engineering the bacterial microcompartment shell protein EutM from Salmonella enterica. Here, we sought to expand this work by developing a toolbox of EutM proteins with different properties, with the potential to be used for future immobilization of enzymes...
July 31, 2018: Applied Microbiology and Biotechnology
Matthias Schapfl, Shiromi Baier, Alexander Fries, Sascha Ferlaino, Simon Waltzer, Michael Müller, Georg A Sprenger
Carboligations catalyzed by aldolases or thiamine diphosphate (ThDP)-dependent enzymes are well-known in biocatalysis to deliver enantioselective chain elongation reactions. A pyruvate-dependent aldolase (2-oxo-3-deoxy-6-phosphogluconate aldolase [EDA]) introduces a chiral center when reacting with the electrophile, glyoxylic acid, delivering the (S)-enantiomer of (4S)-4-hydroxy-2-oxoglutarate [(S)-HOG]. The ThDP-dependent enzyme MenD (2-succinyl-5-enol-pyruvyl-6-hydroxy-3-cyclohexene-1-carboxylate synthase (SEPHCHC synthase)) enables access to highly functionalized substances by forming intermolecular C-C bonds with Michael acceptor compounds by a Stetter-like 1,4- or a benzoin-condensation 1,2-addition of activated succinyl semialdehyde (ThDP adduct formed by decarboxylation of 2-oxoglutarate)...
July 31, 2018: Applied Microbiology and Biotechnology
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