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biocatalysis and enzyme

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, we examined a canonical microreactor design for heterogeneously catalyzed continuous biotransformations, featuring flow microchannels that contain the enzyme immobilized on their wall surface. We use glycosylations by sucrose phosphorylase 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
Shuiqin Jiang, Dongzhi Wei
The development and application of industrial enzymes have penetrated major industrial fields. China faces a major challenge as a large country in applying enzyme but a small one in producing enzyme. Biocatalysis has become an important technology and strategy of industrial development in the world since chemical catalysis encounters the crises from resource, energy and environment. The application of efficient and clean biocatalysis is one of the important ways to realize the sustainable development of chemical industry and to modernize the fermentation industry...
July 25, 2018: Sheng Wu Gong Cheng Xue Bao, Chinese Journal of Biotechnology
Donya Valikhani, Juan M Bolivar, Alexander Dennig, Bernd Nidetzky
Cytochrome P450 monooxygenases (P450s) promote hydroxylations in a broad variety of substrates. Their prowess in C-H bond functionalization renders P450s promising catalysts for organic synthesis. However, operating P450 reactions involves complex management of the main substrates, O2 and NADPH reducing equivalents against an overall background of low operational stability. Whole-cell biocatalysis, although often used, offers no general solution to these problems. Herein, we present the design of a tailor-made, self-sufficient, operationally stabilized and recyclable P450 catalyst on porous solid support...
July 23, 2018: Biotechnology and Bioengineering
Jon Del Arco, Jesús Fernández-Lucas
Due to their similarity to natural counterparts, nucleic acid derivatives (nucleobases, nucleosides, and nucleotides, among others) are interesting molecules for pharmaceutical, biomedical, or food industries. For this reason, there is increasing worldwide demand for the development of efficient synthetic processes for these compounds. Chemical synthetic methodologies require numerous protection-deprotection steps and often lead to the presence of undesirable by-products or enantiomeric mixtures. These methods also require harsh operating conditions, such as the use of organic solvents and hazard reagents...
July 19, 2018: Applied Microbiology and Biotechnology
Dieter M Scheibel, Ivan Gitsov
The aim of this study is to develop efficient enzyme immobilization media that will enable the reuse of the biocatalysts over multiple cycles, increase their thermal stability, and attenuate their activity toward hydrophobic substrates for "green" transformations in aqueous media. For this purpose, amphiphilic AB and ABA block copolymers were synthesized and tested with laccase (a multicopper oxidase). In all cases, the hydrophilic B block consisted of poly(ethylene glycol), PEG, with molecular masses of 3, 5, 13, 20, or 13 kDa poly(ethylene oxide)...
February 28, 2018: ACS Omega
Xue W Diefenbach, Iman Farasat, Erik D Guetschow, Christopher J Welch, Robert T Kennedy, Shuwen Sun, Jeffrey C Moore
Directed Evolution is a key technology driving the utility of biocatalysis in pharmaceutical synthesis. Conventional approaches to Directed Evolution are conducted using bacterial cells expressing enzymes in microplates, with catalyzed reactions measured by HPLC, high-performance liquid chromatography-mass spectrometry (HPLC-MS), or optical detectors, which require either long cycle times or tailor-made substrates. To better fit modern, fast-paced process chemistry development where solutions are rapidly needed for new substrates, droplet microfluidics interfaced with electrospray ionization (ESI)-MS provides a label-free high-throughput screening platform...
February 28, 2018: ACS Omega
Maria F Villegas-Torres, John M Ward, Frank Baganz
Chiral amino alcohols are compounds of pharmaceutical interest as they are building blocks of sphingolipids, antibiotics, and antiviral glycosidase inhibitors. Due to the challenges of chemical synthesis we recently developed two TK-TAm reaction cascades using natural and low cost feedstocks as substrates: a recycling cascade comprising of 2 enzymes and a sequential 3-step enzyme cascade yielding 30% and 1% conversion, respectively. In order to improve the conversion yield and aid the future host strain engineering for whole cell biocatalysis, we used a combination of microscale experiments and statistical experimental design...
September 10, 2018: Journal of Biotechnology
M C Tamayo-Ordóñez, B A Ayil-Gutiérrez, Y J Tamayo-Ordóñez, L C Rodríguez-Zapata, M Monforte-González, E A De la Cruz-Arguijo, M J García-Castillo, L F Sánchez-Teyer
Several of the over 200 known species of Agave L. are currently used for production of distilled beverages and biopolymers. The plants live in a wide range of stressful environments due to their resistance to abiotic stress (drought, salinity, extreme temperature) and pathogens, which gives the genus potential for germplasm conservation and biotechnological applications that may minimize economic losses due to global climate change. However, the limited knowledge in the genus of genome structure and organization hampers development of potential improved biotechnological applications by means of genetic manipulation and biocatalysis...
July 16, 2018: Biotechnology Progress
Alex P S Brogan, Liem Bui-Le, Jason P Hallett
The increasing requirement to produce platform chemicals and fuels from renewable sources means advances in biocatalysis are rapidly becoming a necessity. Biomass is widely used in nature as a source of energy and as chemical building blocks. However, recalcitrance towards traditional chemical processes and solvents provides a significant barrier to widespread utility. Here, by optimizing enzyme solubility in ionic liquids, we have discovered solvent-induced substrate promiscuity of glucosidase, demonstrating an unprecedented example of homogeneous enzyme bioprocessing of cellulose...
August 2018: Nature Chemistry
Joshua Britton, Sudipta Majumdar, Gregory A Weiss
The continuous flow synthesis of active pharmaceutical ingredients, value-added chemicals, and materials has grown tremendously over the past ten years. This revolution in chemical manufacturing has resulted from innovations in both new methodology and technology. This field, however, has been predominantly focused on synthetic organic chemistry, and the use of biocatalysts in continuous flow systems is only now becoming popular. Although immobilized enzymes and whole cells in batch systems are common, their continuous flow counterparts have grown rapidly over the past two years...
June 20, 2018: Chemical Society Reviews
Huan Wang, Ze Zhao, Yuxiao Liu, Changmin Shao, Feika Bian, Yuanjin Zhao
Mimicking subcellular compartments containing enzymes in organisms is considered a promising approach to substitute for missing or lost cellular functions. Inspired by the multicompartment structures of cellular architectures, we present a novel multienzyme system based on hollow hydrogel microcapsules with flexible enzymatic inverse opal particles. Benefiting from the precise operation capability of the microfluidic electrospray and the remarkable structural color marks in the inverse opal particles, we developed a multienzyme system with controllable number, type, and spatial arrangement of the encapsulated enzymes...
June 2018: Science Advances
Min Shen, Xin Ju, Xinqi Xu, Xuemei Yao, Liangzhi Li, Jiajia Chen, Cuiying Hu, Jiaolong Fu, Lishi Yan
In this study, we attempted to find new and efficient microbial enzymes for producing rare sugars. A ribose-5-phosphate isomerase B (OsRpiB) was cloned, overexpressed, and preliminarily purified successfully from a newly screened Ochrobactrum sp. CSL1, which could catalyze the isomerization reaction of rare sugars. A study of its substrate specificity showed that the cloned isomerase (OsRpiB) could effectively catalyze the conversion of L-rhamnose to L-rhamnulose, which was unconventional for RpiB. The optimal reaction conditions (50°C, pH 8...
May 8, 2018: Journal of Microbiology and Biotechnology
Min Kim, Seung Cheol Jee, Jung-Suk Sung, Avinash A Kadam
Owing to the ubiquitous availability and simple biocatalysis, the anti-proliferative laccase holds enormous opportunities for anti-cancer applications. However, accessing efficient and specific (super-magnetically targetable) new delivery system for anti-proliferative laccase is vital step towards laccase based anti-cancer approach. Therefore, in this investigation, super-magnetized (Fe3 O4 ) and chitosan (CS) functionalized halloysite nanotubes (HNTs) (termed as Fe3 O4 -HNTs-CS) was facile synthesized. Further, laccase from Trametes versicolor was immobilized on Fe3 O4 -HNTs-CS (termed as Fe3 O4 -HNTs-CS-Lac)...
June 18, 2018: International Journal of Biological Macromolecules
Shan Chen, Jonatan C Campillo-Brocal, Per Berglund, Maria Svedendahl Humble
The amine transaminase from Vibrio fluvialis (Vf-ATA) is an attractive enzyme with applications within Biocatalysis for the preparation of chiral amines. Various catalytic properties of Vf-ATA have been investigated, but a biophysical characterization of its stability has been lacking. Today, the industrial application of Vf-ATA is limited by its low operational stability. In order to enhance the knowledge regarding the structural stability of ATAs, general characterizations of different ATAs are required. In this work, the stability of Vf-ATA was explored...
June 12, 2018: Journal of Biotechnology
Kyle F Biegasiewicz, Simon J Cooper, Megan A Emmanuel, David C Miller, Todd K Hyster
Strategies that provide enzymes with the ability to catalyse non-natural reactions are of considerable synthetic value. Photoredox catalysis has proved adept at expanding the synthetic repertoire of existing catalytic platforms, yet, in the realm of biocatalysis it has primarily been used for cofactor regeneration. Here we show that photoredox catalysts can be used to enable new catalytic function in nicotinamide-dependent enzymes. Under visible-light irradiation, xanthene-based photocatalysts enable a double-bond reductase to catalyse an enantioselective deacetoxylation...
June 11, 2018: Nature Chemistry
Shaohua Li, Aihua Zhang, Kelly Zatopek, Saba Parvez, Andrew F Gardner, Ivan R Corrêa, Christopher J Noren, Ming-Qun Xu
Covalent immobilization of enzymes on solid supports provides an alternative approach to homogeneous biocatalysis by adding the benefits of simple enzyme removal, improved stability, and adaptability to automation and high-throughput applications. Nevertheless, immobilized (IM) enzymes generally suffer from reduced activity compared to their soluble counterparts. The nature and hydrophobicity of the supporting material surface can introduce enzyme conformational change, spatial confinement, and limited substrate accessibility, all of which will result in loss of the immobilized enzyme activity...
July 18, 2018: Bioconjugate Chemistry
Victoria McCarl, Mark V Somerville, Mai-Anh Ly, Rebecca Henry, Elissa F Liew, Neil L Wilson, Andrew J Holmes, Nicholas V Coleman
Alkene monooxygenases (MOs) are soluble di-iron-containing enzymes found in bacteria that grow on alkenes. Here, we report improved heterologous expression systems for the propene MO (PmoABCD) and ethene MO (EtnABCD) from Mycobacterium chubuense strain NBB4. Strong functional expression of PmoABCD and EtnABCD was achieved in Mycobacterium smegmatis mc2 155, yielding epoxidation activities (62 and 27 nmol/min/mg protein, respectively) higher than any reported to date for heterologous expression of a di-iron MO system...
August 1, 2018: Applied and Environmental Microbiology
Fabián Garzón-Posse, Liliana Becerra-Figueroa, José Hernández-Arias, Diego Gamba-Sánchez
Currently, the power and usefulness of biocatalysis in organic synthesis is undeniable, mainly due to the very high enantiomeric excess reached using enzymes, in an attempt to emulate natural processes. However, the use of isolated enzymes has some significant drawbacks, the most important of which is cost. The use of whole cells has emerged as a useful strategy with several advantages over isolated enzymes; for this reason, modern research in this field is increasing, and various reports have been published recently...
May 25, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
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