Oxidative agents peroxidases

N—Fe(IV)Por complexes. Oxo iron(IV) porphyrin cation radical complexes, [O—Fe(IV)Por ], are important intermediates in oxygen atom transfer reactions. Compound I of the enzymes catalase and peroxidase have this formulation, as does the active intermediate in the catalytic cycle of cytochrome P Q. Similar intermediates are invoked in the extensively investigated hydroxylations and epoxidations of hydrocarbon substrates cataly2ed by iron porphyrins in the presence of such oxidizing agents as iodosylbenzene, NaOCl, peroxides, and air. 

Support for this conclusion is provided by the hydroperoxide specificity of BP oxidation. The scheme presented in Figure 6 requires that the same oxidizing agent is generated by reaction of h2°2/ peroxy acids, or alkyl hydroperoxides with the peroxidase. Oxidation of any compound by the iron-oxo intermediates should be supported by any hydroperoxide that is reduced by the peroxidase. This is clearly not the case for oxidation of BP by ram seminal vesicle microsomes as the data in Figure 7 illustrate. Quinone formation is supported by fatty acid hydroperoxides but very poorly or not at all by simple alkyl hydroperoxides or H2C>2. The fact that... 

The mechanistic aspects of peroxidase-like activity of Fem-TAMLs discussed so far concerned mainly the activation by 1 of primary oxidizing agents, such as in Table VI, characterized by... 

The luminol reaction has been used for the determination of oxidizing agents such as hydrogen peroxide, for enzymes such as peroxidase and xanthine oxidase, and for metal ions such as copper or cobalt that catalyze this CL reaction [24],... 

Oxidizing agents (peroxides and peroxidases), antimicrobial peptides, and monoclonal antibodies also kill or inactivate sexually transmitted pathogens. However, these compounds are found naturally in the vagina and are often introduced to enhance the natural defense mechanisms, and are described below. 

In a study using a commercially available horseradish peroxidase preparation, Stuart and co-workers accomplished the conversion of 3, 4 -anhydrovinblastme (51) to leurosine (52) in a maximum yield of 65% (54). This conversion can be carried out by a variety of oxidizing agents including... 

In the absence of hydrogen peroxide, the final oxidizing agent in the peroxidase enzyme system, homoorientaline (138), is transformed to the one-hydroxy derivative 139 by potato peel homogenate (100). The related benzylisoquinoline reticuline (88) is also hydroxylated at saturated carbon... 

Fergusson RR (1956) On the oxidation of peroxidase by one-electron oxidizing agents. J Am Chem Soc 78 741-745... 

Fig. 9.4 In situ production of hydrogen peroxide by glucose oxidation catalyzed by glucose oxidase. The enzymatically generated hydrogen peroxide is then the oxidizing agent for the oxidation of reducing substrates by peroxidases...

Peroxide A compound containing the —O—O— group. They are strong oxidizing agents. When produced accidentally in the body as a result of a carbohydrate being oxidized, the enzymes catalase and peroxidase in the blood immediately decompose it to prevent damage to body cells. 

Undoubtedly, this broad range of substrate specificity is mainly determined by the strong oxidizing potentials of the activated intermediates of peroxidases. Col and Coll, which make them suitable oxidizing agents for all chemicals donating one electron or a hydrogen atom. 

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