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Enzyme immobilization

Jeong Eun Hyeon, Sang Kyu Shin, Sung Ok Han
The utilization of scaffolds for enzyme immobilization involves advanced bionanotechnology applications in biorefinery fields, which can be achieved by optimizing the function of various enzymes. This review presents various current scaffolding techniques based on proteins, microbes and nanomaterials for enzyme immobilization, as well as the impact of these techniques on the biorefinery of lignocellulosic materials. Among them, architectural scaffolds have applied to useful strategies for protein engineering to improve the performance of immobilized enzymes in several industrial and research fields...
October 26, 2016: Biotechnology Journal
Si Cheng, Jie Sun, Junxing Yang, Jianqiang Lv, Feng Wu, Yanxing Lin, Lishan Liao, Yiyou Ye, Chenfu Cao, Liurong Fang, Qunyi Hua
A fast and ultrasensitive test-strip system combining quantum dots (QDs) with a lateral-flow immunoassay strip (LFIAS) was established for detection of Peste des petits ruminants virus (PPRV) antibody. The highly luminescent water-soluble carboxyl-functionalized QDs were used as the signal output and were conjugated to streptococcal protein G (SPG), which was capable of binding to immunoglobulin G (IgG) from many species through an amide bond to capture the target PPRV IgGs. The PPRV N protein, which was immobilized on the detection zone of the test strip, was expressed by transfecting recombinant Bacmid-PPRV-N with Lipofect into Sf9 insect cells...
October 25, 2016: Analytical and Bioanalytical Chemistry
Muhammad Azhar Hayat Nawaz, Sajid Rauf, Gaelle Catanante, Mian Hasnain Nawaz, Gilvanda Nunes, Jean Louis Marty, Akhtar Hayat
Thin films of organic moiety functionalized carbon nanotubes (CNTs) from a very well-dispersed aqueous solution were designed on a screen printed transducer surface through a single step directed assembly methodology. Very high density of CNTs was obtained on the screen printed electrode surface, with the formation of a thin and uniform layer on transducer substrate. Functionalized CNTs were characterized by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and Brunauer-Emmett- Teller (BET) surface area analyzer methodologies, while CNT coated screen printed transducer platform was analyzed by scanning electron microscopy (SEM), atomic force microscopy (AFM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)...
October 6, 2016: Sensors
Cheau Yuaan Tan, Hidehiko Hirakawa, Risa Suzuki, Tomoaki Haga, Fumiya Iwata, Teruyuki Nagamune
Bacterial cytochrome P450s (P450s), which catalyze regio- and stereoselective oxidations of hydrocarbons with high turnover rates, are attractive biocatalysts for fine chemical production. Enzyme immobilization is needed for cost-effective industrial manufacturing. However, immobilization of P450s is difficult because electron-transfer proteins are involved in catalysis and anchoring these can prevent them from functioning as shuttle molecules for carrying electrons. We studied a heterotrimeric protein-mediated co-immobilization of a bacterial P450, and its electron-transfer protein and reductase...
October 26, 2016: Angewandte Chemie
Se Hyeon Park, Feilicia Soetyono, Hyung Kwoun Kim
Lysine decarboxylase (CadA) converts L-lysine into cadaverine (1,5-pentanediamin), which is an important platform chemical with many industrial applications. Although there have been many efforts to produce cadaverine through the soluble CadA enzyme or Escherichia coli whole cells overexpressing the CadA enzyme, there have been few reports concerning the immobilization of the CadA enzyme. Here, we have prepared a cross-linked enzyme aggregate (CLEA) of E. coli CadA and performed bioconversion using CadA(CLEA)...
October 25, 2016: Journal of Microbiology and Biotechnology
Shicheng Lei, Minhao Xie, Bing Hu, Li Zhou, Yi Sun, Muhammad Saeeduddin, Hongcheng Zhang, Xiaoxiong Zeng
In the present study, pear polyphenol oxidase (PPO) was purified, immobilized and applied for the synthesis of theaflavin-3,3'-digallate (TF3). Firstly, PPO of pear (Pyrus bretschneideri Rehd cv. Huangguan) was purified 24.36-fold in specific activity with a recovery of 6.77% by sequential use of precipitation with 70% saturated ammonium sulfate and chromatography of DEAE-Sepharose Fast Flow column. The purified pear PPO, found to be a dimer of identical subunits of molecular mass 35kDa, was then successfully immobilized onto Fe3O4/chitosan nanoparticles via glutaraldehyde coupling reaction...
October 22, 2016: International Journal of Biological Macromolecules
Gandhali Bapat, Chaitali Labade, Amol Chaudhari, Smita Zinjarde
Silica nanoparticles (SiNPs) find applications in the fields of drug delivery, catalysis, immobilization and sensing. Their synthesis can be mediated in a facile manner and they display broad range compatibility and stability. Their existence in the form of spheres, wires and sheets renders them suitable for varied purposes. This review summarizes the use of silica nanostructures in developing techniques for extraction, detection and degradation of pesticides. Silica nanostructures on account of their sorbent properties, porous nature and increased surface area allow effective extraction of pesticides...
June 10, 2016: Advances in Colloid and Interface Science
Jie Yang, Yonghui Lin, Xiaodan Yang, Tzi Bun Ng, Xiuyun Ye, Juan Lin
Magnetic cross-linked enzyme aggregates (M-CLEAs) were prepared for Cerrena laccase and used in antibiotic treatment. Of the seven antibiotics examined in this study, Cerrena laccase M-CLEAs were most effective in degradation of tetracycline (TC) and oxytetracycline (OTC), followed by ampicillin, sulfamethoxazole and erythromycin. The redox mediator ABTS was not able to improve efficiencies of degradation of TC and OTC. Cerrena laccase at 40U/mL eliminated 100μg/mL TC at pH 6 and 25°C in 48h in the absence of a redox mediator, with over 80% degradation occurring within the first 12h...
October 11, 2016: Journal of Hazardous Materials
Clare F Megarity, Julian Esselborn, Suzannah V Hexter, Florian Wittkamp, Ulf-Peter Apfel, Thomas Happe, Fraser A Armstrong
Protein film electrochemistry (PFE) has been used to study the assembly of the complex 6Fe active site of [FeFe]-hydrogenases (known as the H-cluster) from its precursors the [4Fe 4S] domain that is already coordinated within the host and the 2Fe domain that is presented as a synthetic water-soluble complex stabilized by an additional CO. Not only does PFE allow control of redox states via the electrode potential, but the immobilized state of the enzyme facilitates control of extremely low concentrations of the 2Fe complex...
October 24, 2016: Journal of the American Chemical Society
Timothy K Lee, Kevin Meng, Handuo Shi, Kerwyn Casey Huang
The peptidoglycan cell wall is an integral organelle critical for bacterial cell shape and stability. Proper cell wall construction requires the interaction of synthesis enzymes and the cytoskeleton, but it is unclear how the activities of individual proteins are coordinated to preserve the morphology and integrity of the cell wall during growth. To elucidate this coordination, we used single-molecule imaging to follow the behaviours of the two major peptidoglycan synthases in live, elongating Escherichia coli cells and after perturbation...
October 24, 2016: Nature Communications
Kourosh Abdollahi, Farshad Yazdani, Reza Panahi
Magnetic nanoparticles (MNPs) were synthesized using the chemical co-precipitation method. Then the nanoparticles were coated with silica via hydrolysis of tetraethyl orthosilicate using the sol-gel process. The silica coated magnetic nanoparticles were amine-functionalized with 3-aminopropyltriethoxysilane/ethanol solution. Subsequently, the nanoparticles were added to a solution of cyanuric chloride in tetrahydrofuran to synthesize cyanuric chloride-functionalized magnetic nanoparticles (Cy-MNPs). For covalent immobilization of tyrosinase, Cy-MNPs were added to a freshly prepared tyrosinase solution and the mixture was shaken...
October 19, 2016: International Journal of Biological Macromolecules
Haiyun Wu, Hitoshi Ohnuki, Shirei Ota, Masataka Murata, Yasutoshi Yoshiura, Hideaki Endo
Fishes display a wide variation in their physiological responses to stress, which is clearly evident in the plasma corticosteroid changes, chiefly cortisol levels in fish. As a well-known indicator of fish stress, a simple and rapid method for detecting cortisol changes especially sudden increases is desired. In this study, we describe an enzyme-functionalized label-free immunosensor system for detecting fish cortisol levels. Detection of cortisol using amperometry was achieved by immobilizing both anti-cortisol antibody (selective detection of cortisol) and glucose oxidase (signal amplification and non-toxic measurement) on an Au electrode surface with a self-assembled monolayer...
October 4, 2016: Biosensors & Bioelectronics
K Thenmozhi, S Sriman Narayanan
The enzyme horseradish peroxidase and the water-soluble mediator toluidine blue were covalently immobilized to 3-aminopropyl trimethoxy silane precursor through glutaraldehyde crosslinker. A rigid ceramic composite electrode was fabricated from this modified silane along with graphite powder, which resulted in an amperometric biosensor for H2O2. The electrochemical behaviour of the modified biosensor was monitored using cyclic voltammetry in the potential range of 0.2V to -0.4V vs SCE. The biosensor exhibited a stable voltammogram with cathodic peak at -0...
January 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
Helen Conceição Ferraz, Daniela Ferreira Machado, Neuman Solange de Resende
This work demonstrates the successful modification of screen-printed electrodes using functionalized titanate nanowires for producing a peroxide biosensor. Titanate nanowires were synthesized by the hydrothermal method and characterized using physico-chemical techniques. The surface of the nanowires was modified with (3-aminopropyl)trimethoxysilane and glutaraldehyde to immobilize horseradish peroxidase through covalent bound, obtaining a surface coverage of 1.62mg of enzyme/m(2). The surface of screen-printed carbon electrodes was modified with peroxidase-containing nanowires...
January 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
V L Sirisha, Ankita Jain, Amita Jain
Immobilized enzymes can be used in a wide range of processes. In recent years, a variety of new approaches have emerged for the immobilization of enzymes that have greater efficiency and wider usage. During the course of the last two decades, this area has rapidly expanded into a multidisciplinary field. This current study is a comprehensive review of a variety of literature produced on the different enzymes that have been immobilized on various supporting materials. These immobilized enzymes have a wide range of applications...
2016: Advances in Food and Nutrition Research
Michael J Cooney
Enzyme kinetics is the study of the chemical reactions that are catalyzed by enzymes, with a focus on their reaction rates. The study of an enzyme's kinetics considers the various stages of activity, reveals the catalytic mechanism of this enzyme, correlates its value to assay conditions, and describes how a drug or a poison might inhibit the enzyme. Victor Henri initially reported that enzyme reactions were initiated by a bond between the enzyme and the substrate. By 1910, Michaelis and Menten were advancing their work by studying the kinetics of an enzyme saccharase which catalyzes the hydrolysis of sucrose into glucose and fructose...
2017: Methods in Molecular Biology
Ross D Milton
Electrochemically-active polymers (redox polymers) are useful tools for simultaneous immobilization and electron transfer of enzymes at electrode surfaces, which also serve to increase the localized concentration of the biocatalyst. The properties of the employed redox couple must be compatible with the target biocatalyst from both an electrochemical (potential) and biochemical standpoint. This chapter details the synthesis of a naphthoquinone-functionalized redox polymer (NQ-LPEI) that is used to immobilize and electronically communicate with flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH), yielding an enzymatic bioanode that is able to deliver large catalytic current densities for glucose oxidation at a relatively low associated potential...
2017: Methods in Molecular Biology
David P Hickey
Enzymatic glucose biosensors and biofuel cells make use of the electrochemical transduction between an oxidoreductase enzyme, such as glucose oxidase (GOx), and an electrode to either quantify the amount of glucose in a solution or generate electrical energy. However, many enzymes including GOx are not able to electrochemically interact with an electrode surface directly, but require an external electrochemical relay to shuttle electrons to the electrode. Ferrocene-modified linear poly(ethylenimine) (Fc-LPEI) redox polymers have been designed to simultaneously immobilize glucose oxidase (GOx) at an electrode and mediate electron transfer from their flavin adenine dinucleotide (FAD) active site to the electrode surface...
2017: Methods in Molecular Biology
Gaige R VandeZande, Jasmine M Olvany, Julia L Rutherford, Michelle Rasmussen
Enzymatic electrodes are becoming increasingly common for energy production and sensing applications. Research over the past several decades has addressed a major issue that can occur when using these biocatalysts, i.e., slow heterogeneous electron transfer, by incorporation of a redox active species to act as an electron shuttle. There are several advantages to immobilizing both the enzyme and mediator at the enzyme surface, including increased electron transfer rates, decreased enzyme leaching, and minimized diffusion limitations...
2017: Methods in Molecular Biology
Nenad B Milosavić, Radivoje M Prodanović, Dušan Velićković, Aleksandra Dimitrijević
One of the most used procedures for enzyme stabilization is immobilization. Although immobilization on solid supports has been pursued since the 1950s, there are no general rules for selecting the best support for a giving application. A macroporous copolymer of ethylene glycol dimethacrylate and glycidyl methacrylate (poly (GMA-co-EGDMA)) is a carrier consisting of macroporous beads for immobilizing enzymes of industrial potential for the production of fine chemicals and pharmaceuticals.
2017: Methods in Molecular Biology
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