Peroxidase direct electron transfer

Biosensors based on direct electron transfer of horseradish peroxidase... 

J. Zhao, R.W. Henkens, J. Stonehuerner, J.P. O Daly, and A.L. Crumbliss, Direct electron-transfer at horseradish-peroxidase colloidal gold modified electrodes. J. Electroanal. Chem. 327, 109-119 (1992). 

X.H. Chen, C.M. Ruan, J.L. Kong, and J.Q. Deng, Characterization of the direct electron transfer and bioelectrocatalysis of horseradish peroxidase in DNA film at pyrolytic graphite electrode. Anal. Chim. 

Direct electron transfer has also been achieved with many metalloproteins such as cytochrome C, horseradish peroxidase, microperoxidase (MP-11), myoglobin, hemoglobin, catalase, azurin, and so on, immobilized on different CNT-modified electrodes [45, 61, 144—153]. 

Lu, X., Zhang, Q., Zhang, L., and Li, J., Direct electron transfer of horseradish peroxidase and its biosensor based on chitosan and room temperature ionic liquid, Electrochem. Commun., 8,874-878,2006. 

As pointed out by Gorton and co-workers [19,65], this process is usually referred to a direct electron transfer (DET), that is, when an electrode substitutes the electron donor substrates in a common peroxidase reaction cycle (Eqs. (17.8)-(17.10)). When an electron donor (SH), such as phenolic compounds and the catecholamines shown in Tables 17.2 and 17.4, is present in a peroxidase-electrode system, both processes can occur simultaneously [29,30,43,48,52-54] and the oxidized donor S is reduced electrochemically by the electrode as shown in the following reaction ... 

First examples of the amperometric detection of H202 accomplished in such a range were based on the use of an enzyme, namely horseradish peroxidase (HRP), a prototypical hemeprotein peroxidase, which catalyses the reduction of H202 and due to its peculiar structure, allows direct electron transfer between its active site and the electrode surface at low applied potential [14 17]. This approach, although it shows good sensitivity and accuracy, suffers from some important shortcomings such as low stability and the limited binding of HRP to solid surfaces. 

The phenomenon of bioelectrical catalysis with direct electron transfer from electrode to enzyme active site was primarily observed in the study of electrochemical oxygen reduction in the presence of a copper-containing oxidase - laccase, adsorbed on electrodes of different origins. This work was developed with peroxidase and hydrogenase application as the working components [2],... 

Gold nanoparticles have been used to immobilize micro-peroxidase 11,46 tyrosinase,47 and hemoglobin48 to construct amperometric sensors, while silver nanoparticles have been used to enhance electron transfer of cytochrome c and myoglobin onto pyrolitic graphite electrodes.49 The use of semiconductor and oxide nanoparticles has also been reported, such as horseradish peroxidase (HRP) on TiC>2 nanoparticles,50 as well as Fe304 and MnC>4 nanoparticles to immobilize and facilitate direct electron transfer.51... 

Lu X, Zou G, Li J (2007) Hemoglobin entrapped within a layered spongy C03O4 based nanocomposite featuring direct electron transfer and peroxidase activity. J Mater Chem 17 1427-1432... 

Liu L, Zhao F, Liu L et al (2009) Improved direct electron transfer and electrocatalytic activity of horseradish peroxidase immobilized on gemini surfactant-polyvinyl alcohol composite film. Colloid Surf B Biointerf 68 93-97... 

The ability of these enzymes to contact directly the electrode is attributed to the peripheral location of the redox center. A detailed kinetic study [11] of the peroxidase-catalyzed reduction of H2O2 revealed that 42 % of the enzyme molecules are aligned on the electrode surface in a configuration where the redox heme site is accessible for direct electron transfer. Other enzymes possess two redox sites, and electron transfer proceeds vectorially from a peripheral site to an inner component. For example, /7-cresol methyl hydroxylase [PCMH, a flavin adenine dinucleotide (FAD)- and heme-containing redox enzyme] affects the direct oxidation of p-cresol to -hydroxybenzaldehyde [12[ ... 

A similar approach was used for the detection of monosaccharides [56] pyranose oxidase delivered a suitable oxidase-based sensor with the hydrogen peroxide being determined again via the direct electron transfer from the carbon paste electrode to the enzyme horseradish peroxidase. In aU bi-enz5mie systems, both the enzymes were entrapped within the carbon paste. These electrodes were used as detectors in a liquid chromatography system allowing the simultaneous determination not only of several carbohydrates but also of ethanol within approximately 20 min. Ethanol production and carbohydrate consumption were monitored on-line during a fermentation of P. stipitis for 16 h (see also Section 11.2.3). 

Ferapontova, E.E., Grigorenko, V.G., Egorov, A., Borchers, T., Ruzgas, T., and Gorton, L. (2001) Direct electron transfer in the system gold electroderecombinant horseradish peroxidases. Journal of Electroanalytical Chemistry, 509... 

Hemoproteins are a broad class of redox-proteins that act as cofactors, e.g. cytochrome c, or as biocatalysts, e.g. peroxidases. Direct ET between peroxidases such as horseradish peroxidase, lactoperoxidase," or chloropcroxidasc"" and electrode surfaces, mainly carbonaceous materials, were extensively studied. The mechanistic aspects related with the immobilized peroxidases on electrode surfaces and their utilization in developing biosensor devices were reviewed in detail. The direct electrical contact of peroxidases with electrodes was attributed to the location of the heme site at the exterior of the protein that yields close contact with the electrode surface even though the biocatalyst is randomly deposited on the electrode. For example, it was reported " that non-oriented randomly deposited horseradish peroxidase on a graphite electrode resulted in 40-50% of the adsorbed biocatalyst in an electrically contacted configuration. For other hemoproteins such as cytochrome c it was found that the surface modification of the electrodes with promoter units such as pyridine units induced the binding of the hemoproteins in an orientation that facilitated direct electron transfer. By this method, the promoter sites induce a binding-ET process-desorption mechanism at the modified electrode. Alternatively, the site-specific covalent attachment of hemoproteins such as cytochrome c resulted in the orientation of the protein on the electrode surfaces and direct ET communication. ... 

Lignin peroxidase catalyzes the degradation of lignin, which is the second most abundant type of biomass on earth . The intermediate compounds of lignin peroxidase may have sufficient oxidation potential to allow direct electron transfer from substrate, unlike horseradish peroxidase where hydrogen atom transfer from substrate to compounds I and II occurs ". 

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