Peroxidases polymer synthesis

Horseradish peroxidase (HRP) is an extracellular plant enzyme that acts in regulation of cell growth and differentiation, polymerization of cell wall components, and the oxidation of secondary metabolites essential for important pathogenic defense reactions. Because of these essential functions, and also because of its stability and ready availability, HRP has attracted considerable attention.13 It has been involved in a number of applications, such as diagnostic assays,14 biosensors,15 bioremediation,16 polymer synthesis,17 and other biotechnological processes.18 More applications in which HRP catalysis is translated into an electrochemical signal are likely to be developed in the near future. 

Blinkovsky AM, Dordick JS (1993) Peroxidase-catalyzed synthesis of lignin-phenol copolymers. J Polym Sci A Polym Chem 31 1839-1846... 

Peroxidases belong to the class of oxidoreductases containing iron (111) and protoporphyrin IX as the prosthetic groups. Peroxidases catalyze the reduction of peroxides and the oxidation of many organic and inorganic compounds. These enzymes are widely used for the removal of phenolic compounds, decolorization of synthetic dyes, deodorization of swine manure, in enzyme immunoassays, for biofuel production and organic and polymer synthesis (Hamid and Rehman, 2009). Peroxidases have also been used for the surface modification of poly-p-phenylene-2,6-benzo-bisthiazole (PBO), polyethylene, and grafting of acrylamide onto kevlar fibers. 

Peroxidase-Catalyzed Synthesis of Functional Phenolic Polymers... 

Prior studies demonstrated that the properties of chemically synthesized polyaniline could be modified by the type of synthesis -electrochemical, chemical, or potential cycling methods (1-5). In addition the optical properties of polyaniline could be controlled by the substituents on the nitrogen or aromatic ring (6,7). Enzyme-catal5rzed polymer syntheses in organic solvents with different amounts of water were described in earlier publications (7-10), and nonlinear optical properties of some of these pol5miers were reported (11). This paper describes the horseradish peroxidase-catalyzed synthesis of polyaniline and the evaluation of its optical properties to determine differences, if any, between this polyaniline and those chemically synthesized. 

This section describes the horseradish peroxidase-catalyzed synthesis of both homo- and copolymers of aromatic polymers based on phenols, naphthols, aniline, and their derivatives. Syntheses of novel optically active polymers are studied by changing the environment in which the enzyme functions, along with the organization of the monomers in the reaction mixture. To this objective, enzyme-catalyzed polymer syntheses are carried out in bulk monophasic conditions in which the solvent is miscible with water, biphasic solvent systems in which the solvents used for the syntheses are not miscible with water, and oil-in-water system in the presence of a detergent called reverse micelles. These experimental approaches are shown schematically in Fig. 4. 

Polymerization of p-alkoxyphenols regioselectively proceeded by HRP catalyst to give PPO (252). Peroxidase-catalyzed synthesis of poly(catechol) was achieved and the iodine-labeled polymer showed low electrical conductivity in the range of 10 -10 S cm (253). 

Figure 10.20 Peroxidase-catalyzed oxidative coupling for polymer synthesis.

Siegel S.M. (1957) Non-enzymic macromolecules as matrices in biological synthesis. The role of polysaccharides in peroxidase catalyzed lignin polymer formation from eugenol // J. Amer. Chem. Soc. V. 79. P. 1628-1632... 

Reihmann, M. and Ritter, H. Synthesis of Phenol Polymers Using Peroxidases. Vol. 194, pp. 1-49. 

Cruz-Silva R, Romero-Garcia J, Angulo-Sanchez J, Ledezma-Perez J, Arias-Martfn E, Moggio I, Flores-Loyola E (2005) Template-free enzymatic synthesis of electrically conducting polyanihne using soybean peroxidase. Eur Polym J 41(5) 1129-1135... 

Alvarez S, Manolache S, Denes F (2003) Synthesis of polyaniline using horseradish peroxidase immobilized on plasma-functionalized polyethylene surfaces as initiator. J Appl Polym Sci 88(2) 369-379... 

Akkara JA, Senecal KJ, Kaplan DL (1991) Synthesis and characterization of polymers produced by horseradish peroxidase in dioxane. J Polym Sci A Polym Chem 29 1561-1574... 

Figure 2.14. Possible reaction sequence of polymer formation from catechol by peroxidase. Reprinted from Dubey, S., Singh, D., and Misra, R. A. (1998). Enzymatic synthesis and various properties of poly(catechol). Enzyme Microb. Technol. 23, 432-437, with permission from Elsevier.

Abstract In this chapter, the engineering aspects of processes catalyzed by peroxidases will be presented. In particular, a discussion of the existing technologies that utilize peroxidases for different purposes, such as the removal of recalcitrant compounds or the synthesis of polymers, is analyzed. In the first section, the essential variables controlling the process will be investigated, not only those that... 

---