Horseradish peroxidase catalyzed polymerization

Tobimatsu, Y. Takano, T. Kamitakahara, H. Nakatsubo, F. Azide ion as a quinone methide scavenger in the horseradish peroxidase catalyzed polymerization of sinapyl alcohol. J. WoodSci. 2008, 54, 87-89. 

A molar equivalent of hydrogen peroxide to monomer and horseradish peroxidase is a well-known redox system that catalyzes the free radical polymerization of phenol, anilines, and their derivatives [6-14]. Horseradish peroxidase-mediated polymerization of styrene and methyl methacrylate, with a monomer (styrene or methyl methacrylate) to hydrogen peroxide ratio of 40 1, did not occur in the absence of 2,4-pentanedione. Therefore, it is likely that this compound is involved in the initiation of free radical formation. A reasonable hypothesis for the horseradish peroxidase-catalyzed polymerization of vinyl monomers is that the enzyme is oxidized by hydrogen peroxide and passes from its native state through two catalytically active forms (Ez and Ezz). Each of these active forms oxidizes the initiator (b-diketone, 2,4-pentanedione) while the enzyme returns to the native form. The Ezz state of enzyme is oxidized by hydrogen peroxide to produce inactive enzyme, Ezzz, which spontaneously reverts to the native form of enzyme. The free radicals produced from the initiator generate radicals in the vinyl monomer to form polymer (Fig. 2). 

Another iUnstration of the MALDI-TOF MS applicability in monitoring polymerization reactions was presented by Xn et al. [99] in the case of the enzymatic polymerization of 4-phenylphenol. Horseradish peroxidase catalyzed polymerization reactions were carried out at room temperature in 50/50 acetone-0.01 M sodium phosphate buffer mixture. The effects of the oxidant... 

Peroxidase-Catalyzed Polymerization of p-Cresol. Large scale polymerizations were carried out in a volume of 250 mL in a 500 mL round bottom flask at 25°C with stirring at ca. 250 rpm. p-Cresol (688 mg, 25 mM) was dissolved in 213 mL dioxane and 37 mL aqueous buffer, pH 7 (0.01 M phosphate) added to give a solution consisting of 85% (v/v) dioxane. Horseradish peroxidase (25 mg, free powder) was added and the reaction was initiated by the addition of 0.28 mL of 30% H2O2 (10 mM). The suspension (peroxidase is insoluble in 85% dioxane) immediately turned yellow and the reaction was allowed to proceed 15 min. The concentrations of p-cresol and reaction products were determined by high performance liquid chromatography (HPLC) with a Ci8-reverse phase column (Waters Associates, Milford, MA). The isocratic solvent used was acetonitrile water (56 44) with... 

Nolte et al 46) produced an artificial enzyme based on the T4 replisome and applied it to the epoxidation of double bonds in synthetic polymers. Smith et al 51) reported that horseradish peroxidase catalyzes the oxidative polymerization of glucuronic acid. In recent literature, many biomimetic macromolecules with enzyme-like structures or functions have been reported including those that are dendrimers 64-66), those that have specified three-dimensional structures or recognition elements created by molecular imprinting 67), and other enzyme mimics 68). 

Recently a new strategy was developed whereby a nuld and highly selective enzymatic method was used to covalently couple the primary hydroxyl group of ascorbic acid with styrene and methyl acrylate monomers, followed by a second enzymatic reaction catalyzed by horseradish peroxidase to polymerize the styrene and acrylate monomers yielding vitamin C functionalized... 

Among other in vitro enzymatic polymerizations that have been studied are the oxidative polymerizations of 2,6-disubstituted phenols to poly(p-phenylene oxide)s (Sec. 2-14b) catalyzed by horseradish peroxidase [Higashimura et al., 2000b] and the polymerization of P-cellobiosyl fluoride to cellulose catalyzed by cellulase [Kobayashi, 1999 Kobayashi et al., 2001],... 

Four methods have been developed for enzyme immobilization (1) physical adsorption onto an inert, insoluble, solid support such as a polymer (2) chemical covalent attachment to an insoluble polymeric support (3) encapsulation within a membranous microsphere such as a liposome and (4) entrapment within a gel matrix. The choice of immobilization method is dependent on several factors, including the enzyme used, the process to be carried out, and the reaction conditions. In this experiment, an enzyme, horseradish peroxidase (donor H202 oxidoreductase EC 1.11.1.7), will be imprisoned within a polyacrylamide gel matrix. This method of entrapment has been chosen because it is rapid, inexpensive, and allows kinetic characterization of the immobilized enzyme. Immobilized peroxidase catalyzes a reaction that has commercial potential and interest, the reductive cleavage of hydrogen peroxide, H202, by an electron donor, AH2 ... 

So far, several oxidoreductases, peroxidase, laccase, polyphenol oxidase (tyrosinase), and so on have been reported to catalyze oxidative polymerization of phenol derivatives among which peroxidase is most often used [165,166]. Peroxidase is an enzyme that catalyzes the oxidation of a donor to an oxidized donor by the action of hydrogen peroxide, liberating two water molecules. Horseradish peroxidase (HRP) is a single-chain p-type hemoprotein that catalyzes the decomposition of hydrogen peroxide at the expense of aromatic proton donors. 

Horseradish peroxidase (HRP, EC 1.11.1.7) catalyzes the ( -dependent oxidation of phenols and amines forming colored polymeric products via radical intermediates. This reaction has been used to detect phenol, bilirubin and aminopyrine (Renneberg et al., 1982). The hydrogen peroxide required was either injected into the measuring cell or generated in the enzyme membrane itself. For the latter reaction, GOD was coimmobilized with HRP. 

Another advantage of this enzyme-catalyzed route to colloidal PAn salts is the considerably higher pH that can be employed compared to the previous chemical and electrochemical polymerization methods. Horseradish peroxidase immobilized on chitosan powder as a solid support has also been found to catalyze the H202 oxidation of aniline to a similar PAn/PSS product, opening up the prospect of enzyme reuse and the design of enzyme reactors for PAn synthesis.104... 

Many efforts have been made to base polymers on furfural made from pentoses.159 The polymers may be useful, but tend to have lower thermal stability than the usual synthetic polymers. Polyesters based on furfural were mentioned earlier. The acid-catalyzed polymerization of furfuryl alcohol is used in foundry cores.160 Furfural has been condensed with cardanol (m-pentadecadienylphenol) from cashew nut shell oil in the presence of other phenols to produce polymeric resins.161 Cardanol and hydrogenated cardanol have been polymerized with horseradish peroxidase to soluble polymers in up to 85% yield.162 Plasticizers that are effective in polyvinyl chloride, such as (12.31), have been made from furfural.163... 

Peroxidase-catalyzed radical formation is by far the most popular and best characterized initiation reaction for enzymatic polymerizations. Particularly horseradish peroxidase (HRP) has been used for a variety of polymerization reactions. 

It is now well-established that some enzyme families, including various peroxidases and laccases, catalyze the polymerization of vinyl monomers and other redox active species such as phenol-type structures. Vinyl polymerization by these redox catalysts has recently been reviewed 93). These catalysts have been used to prepare polyanilines 94) and polyphenols 95,96). A few examples of related research are included in this book. For example. Smith et al (57) described a novel reaction catalyzed by horseradish peroxidase (HRP). In the presence of HRP and oxygen, D-glucuronic acid was polymerized to a high molecular weight (60,000) polyether. However, the authors have not yet illucidated the polyether structure. Two other oxidative biotransformations were discussed above i) the sono-enzymatic polymerization of catechol via laccase 31), and ii) the oxidation of aryl silanes via aromatic dioxygenases 30). 

There have been recent reports of a glucose biosensor based on electroenzyme-catalyzed oxidation of glucose using a horseradish peroxidase-glucose oxidase lying on polymeric membrane. The biosensor has been used with human serum and pharmaceutical samples. 

Table 3 gives the third-order nonlinear optical properties of bioengineered polymers prepared by enzyme-catalyzed polymerization using horseradish peroxidase in biphasic solvent systems. Water-immiscible solvents used for the biphasic media are benzene, chloroform, toluene, tetrahydrofuran, and isooctane. Third-order nonlinear optical properties of homopolymers and copolymers prepared in biphasic solvent systems are similar to those of polymers prepared in monophasic systems. The values of polyaromatic amines solutions measured at 532 nm are one to two orders higher than the x values observed with polyphenolic compounds. Third-order nonlinear optical properties of copolymers of aromatic amines with... 

Enzyme-Catalyzed Polymerization. Horseradish peroxidase (HRP) has been used for the oxidation of a wide variety of compounds, eg, phenol derivatives in the presence of hydroperoxide (44). HRP is a kind of heme glycoprotein that catalyzes the oxidation of phenol to phenoxy radicals. Subsequently, the resulting phenoxy radicals couple each other to oligo or polyphenol derivatives step by step (see Oxidative Polymerization). 

The principle of the polymerization of phenols catalyzed by a peroxidase is explained in the following text for the enzyme horseradish peroxidase (HRP). The mechanism of the HRP catalysis is fairly well understood and has been the subject of many investigations [24,51-54]. HRP catalyzes the one-electron oxidation of phenols by a peroxide to form the corresponding phenoxy radicals. Usually, hydrogen peroxide is used as oxidizing reagent. During this process, two water molecules are formed [55] (Eq. 1) ... 

Scheme 1 Polymerization of phenols catalyzed by horseradish peroxidase (HRP)...

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