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multienzyme system

Zhiping Zhang, Yanzhi He, Yue Huang, Li Ding, Lei Chen, Yaxian Liu, Yesen Nie, Xinyue Zhang
An in vitro multienzyme synthetic system was developed and optimized to efficiently produce kaempferol in a single reaction tube. Two key genes, Atf3h and Atfls1, in the biosynthetic pathway of kaempferol were cloned into a prokaryotic expression vector and overexpressed in Escherichia coli. The recombinant proteins were purified through affinity chromatography and showed activities of flavanone 3-hydroxylase and flavonol synthase, respectively, followed by development of an in vitro synthetic system for producing kaempferol...
July 18, 2018: Journal of Agricultural and Food Chemistry
Xinyun Cao, Tobias Koch, Lydia Steffens, Julia Finkensieper, Renate Zigann, John E Cronan, Christiane Dahl
Many Bacteria and Archaea employ the heterodisulfide reductase (Hdr)-like sulfur oxidation pathway. The relevant genes are inevitably associated with genes encoding lipoate-binding proteins (LbpA). Here, deletion of the gene identified LbpA as an essential component of the Hdr-like sulfur-oxidizing system in the Alphaproteobacterium Hyphomicrobium denitrificans . Thus, a biological function was established for the universally conserved cofactor lipoate that is markedly different from its canonical roles in central metabolism...
July 13, 2018: ELife
Li Zhou, Yu Liu, Hui Shi, Xiaohai Yang, Jin Huang, Songyang Liu, Qiaoshu Chen, Jianbo Liu, Kemin Wang
Spatial organization of multienzyme at specific positions for controlled reaction cascade has attracted wide attentions. Here, we report the construction of a biomimetic enzyme cascade organizing on DNA triangle prism (TP) nanostructures, which enabled efficient catalytical production of nitric oxide (NO) on a single microbead. Two enzymes, glucose oxidase (GOx) and horseradish peroxidase (HRP), were assembled at adjacent locations on DNA TP nanostructure by using DNA-binding protein adaptors with small interenzyme distances...
July 9, 2018: Chembiochem: a European Journal of Chemical Biology
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
Moritz Hunkeler, Anna Hagmann, Edward Stuttfeld, Mohamed Chami, Yakir Guri, Henning Stahlberg, Timm Maier
Acetyl-CoA carboxylase catalyses the ATP-dependent carboxylation of acetyl-CoA, a rate-limiting step in fatty acid biosynthesis1,2 . Eukaryotic acetyl-CoA carboxylases are large, homodimeric multienzymes. Human acetyl-CoA carboxylase occurs in two isoforms: the metabolic, cytosolic ACC1, and ACC2, which is anchored to the outer mitochondrial membrane and controls fatty acid β-oxidation1,3 . ACC1 is regulated by a complex interplay of phosphorylation, binding of allosteric regulators and protein-protein interactions, which is further linked to filament formation1,4-8 ...
June 2018: Nature
Alan T Culbertson, Jacqueline J Ehrlich, Jun-Yong Choe, Richard B Honzatko, Olga A Zabotina
The plant cell wall is primarily a polysaccharide mesh of the most abundant biopolymers on earth. Although one of the richest sources of biorenewable materials, the biosynthesis of the plant polysaccharides is poorly understood. Structures of many essential plant glycosyltransferases are unknown and suitable substrates are often unavailable for in vitro analysis. The dearth of such information impedes the development of plants better suited for industrial applications. Presented here are structures of Arabidopsis xyloglucan xylosyltransferase 1 (XXT1) without ligands and in complexes with UDP and cellohexaose...
June 5, 2018: Proceedings of the National Academy of Sciences of the United States of America
Cyril Lefebvre, Richard Boulon, Manuelle Ducoux, Sabine Gavalda, Françoise Laval, Stevie Jamet, Nathalie Eynard, Anne Lemassu, Kaymeuang Cam, Marie-Pierre Bousquet, Fabienne Bardou, Odile Burlet-Schiltz, Mamadou Daffé, Annaïk Quémard
Mycolic acids (MAs) have a strategic location within the mycobacterial envelope, deeply influencing its architecture and permeability, and play a determinant role in the pathogenicity of mycobacteria. The fatty acid synthase type II (FAS-II) multienzyme system is involved in their biosynthesis. A combination of pull-downs and proteomics analyses led to the discovery of a mycobacterial protein, HadD, displaying highly specific interactions with the dehydratase HadAB of FAS-II. In vitro activity assays and homology modeling showed that HadD is, like HadAB, a hot dog folded (R)-specific hydratase/dehydratase...
April 16, 2018: Scientific Reports
Namrata Singh, Motika Geethika, Sandeep M Eswarappa, Govindasamy Mugesh
Nanomaterials having enzyme-like activity (nanozymes) make them suitable candidates for various biomedical applications. In this study, we demonstrate the morphology-dependent enzyme mimetic activity of Mn3 O4 nanoparticles. It is found that Mn3 O4 nanoparticles mimic the functions of all three cellular antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Interestingly, the nanozyme activity of Mn3 O4 depends on various factors including size, morphology, surface area, and the redox properties of the metal ions...
March 30, 2018: Chemistry: a European Journal
Jean Felix Mukerabigwi, Zhishen Ge, Kazunori Kataoka
Therapeutic nanoreactors have been proposed as nanoplatforms to treat diseases through in situ production of therapeutic agents. When this treatment strategy is applied in cancer therapy, it can efficiently in situ produce the highly toxic anticancer drugs from low-toxic prodrugs or some biomolecules in tumor tissues, which can maximize the therapeutic efficacy with a significantly low systemic toxicity. An ideal therapeutic nanoreactor can provide the reaction space, protect the loaded fragile catalysts, target to the desired pathological site, and be selectively activated...
March 23, 2018: Chemistry: a European Journal
Hui-Lei Yu, Tuo Li, Fei-Fei Chen, Xiao-Jing Luo, Aitao Li, Chao Yang, Gao-Wei Zheng, Jian-He Xu
Biocatalytic C-H amination is one of the most challenging tasks. C-H amination reaction can hardly be driven efficiently by solely one enzyme so far. Thus, enzymatic synergy represents an alternative strategy. Herein, we report an "Artificially Bioamination Pathway" for C-H amination of cyclohexane as a model substrate. Three enzymes, a monooxygenase P450BM3 mutant, an alcohol dehydrogenase ScCR from Streptomyces coelicolor and an amine dehydrogenase EsLeuDH from Exiguobacterium sibiricum, constituted a clean cascade reaction system with easy product isolation...
May 2018: Metabolic Engineering
Qi Zhang, Shuo Chen, Hua Wang, Hongtao Yu
Hydrogen peroxide (H2 O2 ) is a key reactant in the Fenton process. As a byproduct of enzymatic reaction, H2 O2 can be obtained via catalytical oxidation of glucose using glucose oxidase in the presence of O2 . Another oxidation product (gluconic acid) can suitably adjust the microenvironmental pH contributing to the Fe3+ /Fe2+ cycle in the Fenton reaction. Enzymes are extremely efficient at catalyzing a variety of reactions with high catalytic activity, substrate specificity, and yields in living organisms...
March 14, 2018: ACS Applied Materials & Interfaces
Miji Jeon, Hye-Won Kang, Songon An
We have recently demonstrated that the rate-limiting enzymes in human glucose metabolism organize into cytoplasmic clusters to form a multienzyme complex, the glucosome, in at least three different sizes. Quantitative high-content imaging data support a hypothesis that the glucosome clusters regulate the direction of glucose flux between energy metabolism and building block biosynthesis in a cluster size-dependent manner. However, direct measurement of their functional contributions to cellular metabolism at subcellular levels has remained challenging...
February 9, 2018: Scientific Reports
Sujatha Chilakala, Lan Li, Ye Feng, Yan Xu
Study of DNA base composition, DNA adducts and modification in its primary structure is a subject of interest in different fields of scientific research. Various methods like immunochemistry, capillary electrophoretic separation, chromatographic separation coupled with mass spectrometric (LC-MS/MS) detection have been developed for DNA analysis. During the past decade LC-MS/MS has emerged as a more sensitive and selective technique and now frequently used for the analysis of DNA. The workflow for the DNA analysis include DNA extraction, hydrolysis of DNA into mononucleosides and analysis...
April 1, 2018: Analytical Biochemistry
Stuti Bhagat, N V Srikanth Vallabani, Vaithiyalingam Shutthanandan, Mark Bowden, Ajay S Karakoti, Sanjay Singh
Catalytically active individual gold (Au) and cerium oxide (CeO2 ) nanoparticles (NPs) are well known to exhibit specific enzyme-like activities, such as natural catalase, oxidase, superoxide dismutase, and peroxidase enzymes. These activities have been maneuvered to design several biological applications such as immunoassays, glucose detection, radiation and free radical protection and tissue engineering. In biological systems, multienzyme complexes are involved in catalyzing important reactions of essential metabolic processes such as respiration, biomolecule synthesis, and photosynthesis...
March 1, 2018: Journal of Colloid and Interface Science
Aneta Stachowicz, Jakub Siudut, Maciej Suski, Rafał Olszanecki, Ryszard Korbut, Anetta Undas, Jacek R Wiśniewski
Background: It is well known that fibrin network binds a large variety of proteins, including inhibitors and activators of fibrinolysis, which may affect clot properties, such as stability and susceptibility to fibrinolysis. Specific plasma clot composition differs between individuals and may change in disease states. However, the plasma clot proteome has not yet been in-depth analyzed, mainly due to technical difficulty related to the presence of a highly abundant protein-fibrinogen and fibrin that forms a plasma clot...
2017: Clinical Proteomics
James Nicholas Vranish, Mario G Ancona, Scott A Walper, Igor L Medintz
The growing emphasis on green chemistry, renewable resources, synthetic biology, regio-/stereospecific chemical transformations, and nanotechnology for providing new biological products and therapeutics is reinvigorating research into enzymatic catalysis. Although the promise is profound, many complex issues remain to be addressed before this effort will have a significant impact. Prime among these is to combat the degradation of enzymes frequently seen in ex vivo formats following immobilization to stabilize the enzymes for long-term application and to find ways of enhancing their activity...
March 6, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Shuang Li, Shuaishuai Wang, Xuan Fu, Xian-Wei Liu, Peng George Wang, Junqiang Fang
Hyaluronan (HA) is a linear polysaccharide composed of repeating disaccharide units. It has been well documented to play an array of biological functions in cancer events. Here, we reported a sequential one-pot multienzyme (OPME) strategy for in vitro synthesis of HA and its derivatives. The strategy, which combined in situ sugar nucleotides generation with HA chain polymerization, could convert cheap monosaccharides into HA polymers without consuming exogenous sugar nucleotide donors. HA polymers (number-average molecular weight ranged from 1...
December 15, 2017: Carbohydrate Polymers
Ye Yang, Ruiqi Zhang, Bingnan Zhou, Jiayi Song, Ping Su, Yi Yang
The development of new methods for fabricating artificial multienzyme systems has attracted much interest because of the potential applications and the urgent need for multienzyme catalysts. Controlling the enzyme ratio is critical for improving the cooperative enzymatic activity in multienzyme systems. Herein, we introduce a versatile strategy for fabricating a multienzyme system by coimmobilizing horseradish peroxidase (HRP) and glucose oxidase (GOx) on magnetic nanoparticles multifunctionalized with dopamine derivatives through DNA-directed immobilization...
October 12, 2017: ACS Applied Materials & Interfaces
Hai Yu, Yanhong Li, Zhigang Wu, Lei Li, Jie Zeng, Chao Zhao, Yijing Wu, Nova Tasnima, Jing Wang, Huaide Liu, Madhusudhan Reddy Gadi, Wanyi Guan, Peng G Wang, Xi Chen
Helicobacter pylori α1-3/4-fucosyltransferase (Hp3/4FT) was expressed in Escherichia coli at a level of 30 mg L-1 culture and used as a diverse catalyst in a one-pot multienzyme (OPME) system for high-yield production of l-fucose-containing carbohydrates including Lewis antigens such as Lewis a, b, and x, O-sulfated Lewis x, and sialyl Lewis x and human milk fucosides such as 3-fucosyllactose (3-FL), lacto-N-fucopentaose (LNFP) III, and lacto-N-difuco-hexaose (LNDFH) II and III. Noticeably, while difucosylation of tetrasaccharides was readily achieved using an excess amount of donor, the synthesis of LNFP III was achieved by Hp3/4FT-catalyzed selective fucosylation of the N-acetyllactosamine (LacNAc) component in lacto-N-neotetraose (LNnT)...
October 5, 2017: Chemical Communications: Chem Comm
Yan-Jun Liu, Shiaw-Lin Wu, Kerry R Love, William S Hancock
Influenza hemagglutinin is a surface glycoprotein related to virus invasion and host immune system response. Understanding site specific glycosylation of hemagglutinin will increase our knowledge about virus evolution and can improve the design and quality of vaccines. In our study, we used glycoproteomic analysis based on multienzyme digestion followed by LC tandem MS analysis to determine the glycosylation of Influenza hemagglutinin (H1/A/California/04/2009) using the following steps: PNGaseF treatment combined with trypsin or pepsin digestion was used to determine the glycosites and glycan occupancy...
October 17, 2017: Analytical Chemistry
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