569-77-7Relevant articles and documents
Enhanced Activity of Enzymes Encapsulated in Hydrophilic Metal-Organic Frameworks
Liang, Weibin,Xu, Huoshu,Carraro, Francesco,Maddigan, Natasha K.,Li, Qiaowei,Bell, Stephen G.,Huang, David M.,Tarzia, Andrew,Solomon, Marcello B.,Amenitsch, Heinz,Vaccari, Lisa,Sumby, Christopher J.,Falcaro, Paolo,Doonan, Christian J.
, (2019)
Encapsulation of biomacromolecules in metal-organic frameworks (MOFs) can preserve biological functionality in harsh environments. Despite the success of this approach, termed biomimietic mineralization, limited consideration has been given to the chemistry of the MOF coating. Here, we show that enzymes encapsulated within hydrophilic MAF-7 or ZIF-90 retain enzymatic activity upon encapsulation and when exposed to high temperatures, denaturing or proteolytic agents, and organic solvents, whereas hydrophobic ZIF-8 affords inactive catalase and negligible protection to urease.
A low molecular weight hydrogel which exhibits electroosmotic flow and its use as a bioreactor and for electrochromatography of neutral species
Mizrahi, Shaul,Rizkov, Dan,Hayat, Netanel,Lev, Ovadia
, p. 2914 - 2916 (2008)
A low molecular weight hydrogel which exhibits electroosmotic flow is described, and its use for separation and biocatalytic applications that require passage of a solvent stream through the gel is demonstrated. The Royal Society of Chemistry.
Oxidation of ethanol induced by simple polyphenols: Prooxidant property of polyphenols
Inui, Takako,Nakahara, Koichi,Uchida, Masaaki,Miki, Wataru,Unoura, Kei,Kokeguchi, Yuki,Hosokawa, Takahiro
, p. 1201 - 1207 (2004)
The aerobic oxidation of ethanol to acetaldehyde in water is induced by simple polyphenols, such as pyrogallol or catechol, in the presence of FeSO 4-DTPA (N,N,N′,N′′,N′′- diethylenetriaminepentaacetic acid) catalyst. The amount of acetaldehyde formed becomes an indicator of their "prooxidant" ability in terms of the activation of O2. The "prooxidant" ability of pyrogallol is higher than that of catechol. Electron-withdrawing substituents decrease the ability, whereas electron-donating ones enhance it. The "prooxidant" property is exhibited by the total consequence of two processes: hydroxyl radical (OH) generation from O2 and its capture by phenolic compounds.
Biomimetic catalysis of a porous iron-based metal-metalloporphyrin framework
Chen, Yao,Hoang, Tran,Ma, Shengqian
, p. 12600 - 12602 (2012)
A porous metal-metalloporphyrin framework, MMPF-6, based upon an iron(III)-metalated porphyrin ligand and a secondary binding unit of a zirconium oxide cluster was constructed; MMPF-6 demonstrated interesting peroxidase activity comparable to that of the heme protein myoglobin as well as exhibited solvent adaptability of retaining the peroxidase activity in an organic solvent.
Synthesis of reduced graphene oxide-iron nanoparticles with superior enzyme-mimetic activity for biosensing application
Li, Lili,Zeng, Chunmei,Ai, Lunhong,Jiang, Jing
, p. 470 - 477 (2015)
Development of enzyme-mimetic catalysts with sustainability and environmental benignancy has gained considerable attention with the growing demands for large-scale applications in recent years. Here, we demonstrate that the reduced graphene oxide (RGO)-iron nanoparticles (INs) can be utilized as the highly active and cost-effective enzyme-mimetic catalysts for the first time, which have been successfully synthesized by a facile iron-self-catalysis process at room temperature. Benefitting from synergetic effects between RGO and INs, the RGO-INs could efficiently catalyze the oxidization of 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H2O2 to produce a typical color reaction, showing the much better peroxidase-like activity than that of each individual part. The mechanistic insight into the enhanced peroxidase-like activity of the RGO-INs was investigated systematically. On the basis of the enzyme-mimetic activity of the RGO-INs, the simple, sensitive, selective and cost-effective colorimetric assays for the detection of hydrogen peroxide and glucose with naked eyes were successfully established. The RGO-INs showed several prominent advantages, such as facile preparation, low cost, tunability in catalytic activity, and low detection limit, over natural peroxidase or other nanomaterial-based alternatives, holding great potential as enzymatic mimics for biosensing applications.
Surfactant-stabilized small hydrogel particles in oil: Hosts for remarkable activation of enzymes in organic solvents
Das, Dibyendu,Roy, Sangita,Debnath, Sisir,Das, Prasanta Kumar
, p. 4911 - 4922 (2010)
Hydrogels of amino acid based cationic surfactant having C16 tails were used to immobilize heme proteins and enzyme. These hydrogelentrapped proteins/enzyme showed remarkable activation when dispersed in organic solvent. The activation effect (ratio of the activity of the hydrogelentrapped enzyme in organic solvent to the activity of the native enzyme in water) of cytochrome c increased up to 350-fold with varying protein and gelator concentration. Hydrogel-entrapped hemoglobin and horseradish peroxidase (HRP) also showed markedly improved activity in organic solvent. Alteration in the structure of the gelator and its supramolecular arrangement showed that the protein immobilized within amphiphilic networks with larger interstitial space exhibited higher activation. This striking activation of hydrogel-entrapped proteins stems from the following effects: 1) the hydrophilic domain of the amphiphilic networks facilitates accessibility of the enzyme to the water-soluble substrate. 2) the surfactant, as an integral part of the amphiphilic network, assists in the formation of a distinct interface through which reactants and products are easily transferred between hydrophilic and hydrophobic domains. 3) Surfactant gelators help in the dispersion and stabilization of gel matrix into small particles in organic solvent, which enhances the overall surface area and results in improved mass transfer. The activation was dramatically improved up to 675-fold in the presence of nongelating anionic surfactants that helped in disintegration of the gel into further smaller-sized particles. Interestingly, hydrogel-immobilized HRP exhibited about 2000-fold higher activity in comparison to the activity of the suspended enzyme in toluene. Structural changes of the entrapped enzyme and the morphology of the matrix were investigated to understand the mechanism of this activation.
Bioinorganic Nanocomposite Hydrogels Formed by HRP-GOx-Cascade-Catalyzed Polymerization and Exfoliation of the Layered Composites
Liao, Chuan-An,Wu, Qing,Wei, Qing-Cong,Wang, Qi-Gang
, p. 12620 - 12626 (2015)
The mild preparation of multifunctional nanocomposite hydrogels is of great importance for practical applications. We report that bioinorganic nanocomposite hydrogels, with calcium niobate nanosheets as cross-linkers, can be prepared by dual-enzyme-triggered polymerization and exfoliation of the layered composite. The layered HRP/calcium niobate composites (HRP=horseradish peroxidase) are formed by the assembly of the calcium niobate nanosheets with HRP. The dual-enzyme-triggered polymerization can induce the subsequent exfoliation of the layered composite and final gelation through the interaction between polymer chains and inorganic nanosheets. The self-immobilized HRP-GOx enzymes (GOx=glucose oxidase) within the nanocomposite hydrogel retain most of enzymatic activity. Evidently, their thermal stability and reusability can be improved. Notably, our strategy could be easily extended to other inorganic layered materials for the fabrication of other functional nanocomposite hydrogels.
Oxidation of phenyl compounds using strongly stable immobilized-stabilized laccase from Trametes versicolor
Addorisio, Veria,Sannino, Filomena,Mateo, Cesar,Guisan, Jose M.
, p. 1174 - 1180 (2013)
The hydrolysis of phenolic compounds using an immobilized and highly active and stable derivative of laccase from Trametes versicolor is presented. The enzyme was immobilized on aldehyde supports. For this, the enzyme was enriched in amino groups by chemical modification of its carboxyl groups. The aminated enzyme was immobilized with a high recovered activity (over 60%). Aldehyde derivatives were more stable than soluble or aminated-soluble enzyme and the reference derivatives after incubation in different inactivating conditions (high temperatures, different pH values or presence of organic cosolvents). The most stable derivative was obtained immobilizing the chemically aminated enzyme at pH 10 on aldehyde supports with a stabilization factor approximately 280 fold after incubation at pH 7 and 55 C. In addition, it was possible to prepare immobilized derivatives with a maximal enzyme loading of 60 mg g-1 of support. This derivative could be reused for 10 reaction cycles with negligible lost of activity.
A polymer grafted oxidomethoxidovanadium(V) complex of an ONO donor ligand mimicking peroxidase activity
Maurya, Mannar R.,Kumar, Naveen,Chaudhary, Nikita
, p. 103 - 111 (2015)
The reaction between [VIVO(acac)2] and the ONO donor tridentate ligand H2hap-iah (I) [H2hap-iah = Schiff base obtained by the condensation of equimolar amounts of o-hydroxyacetophenone (hap) and indole-3-acetic hydrazide (iah)] in an equimolar ratio under an oxygen atmosphere in refluxing methanol gives [VVO(OMe)(hap-iah)] (1). Treatment of 1 in methanol with H2O2 in the presence of KOH results in the formation of K[VVO(O2)(hap-iah)] (2). Complex 1 has been grafted into chloromethylated polystyrene cross-linked with 5% divinylbenzene {now abbreviated as PS-[VVO(OMe)(hap-iah)] (3)} via covalent bonding through the imino nitrogen atom of the indole group. The two complexes have been characterized by various spectroscopic techniques (IR, electronic, 1H, 13C and 51V NMR, ESI-MS), analytical and thermal studies. The polymer-grafted complex 3 has also been analyzed by field-emission scanning electron micrographs (FE-SEM) as well as energy dispersive X-ray (EDAX) studies. The polymer-grafted complex 3 has been used as a catalyst for the peroxidase-like oxidation of pyrogallol to purpurogallin in pH 7 buffer solution. Its high peroxidase mimicking ability, easy separation from the reaction medium and the reusability, without any considerable decrease in activity, suggest the practical utility of the catalyst.
Unraveling the anti-influenza effect of flavonoids: Experimental validation of luteolin and its congeners as potent influenza endonuclease inhibitors
Albi?ana, Carlos Berenguer,Brynda, Ji?í,Fanfrlík, Jind?ich,Flieger, Miroslav,Hodek, Jan,Karlukova, Elena,Ko?í?ek, Milan,Konvalinka, Jan,Machara, Ale?,Majer, Pavel,Radilová, Kate?ina,Weber, Jan,Zima, Václav
supporting information, (2020/09/09)
The biological effects of flavonoids on mammal cells are diverse, ranging from scavenging free radicals and anti-cancer activity to anti-influenza activity. Despite appreciable effort to understand the anti-influenza activity of flavonoids, there is no clear consensus about their precise mode-of-action at a cellular level. Here, we report the development and validation of a screening assay based on AlphaScreen technology and illustrate its application for determination of the inhibitory potency of a large set of polyols against PA N-terminal domain (PA-Nter) of influenza RNA-dependent RNA polymerase featuring endonuclease activity. The most potent inhibitors we identified were luteolin with an IC50 of 72 ± 2 nM and its 8-C-glucoside orientin with an IC50 of 43 ± 2 nM. Submicromolar inhibitors were also evaluated by an in vitro endonuclease activity assay using single-stranded DNA, and the results were in full agreement with data from the competitive AlphaScreen assay. Using X-ray crystallography, we analyzed structures of the PA-Nter in complex with luteolin at 2.0 ? resolution and quambalarine B at 2.5 ? resolution, which clearly revealed the binding pose of these polyols coordinated to two manganese ions in the endonuclease active site. Using two distinct assays along with the structural work, we have presumably identified and characterized the molecular mode-of-action of flavonoids in influenza-infected cells.
