Metabolism of Organic Compounds

Microorganisms can convert toxic organics into nontoxic and inactive compounds. This process is referred to as detoxication or detoxification. The inactive compounds can undergo the following  

Oxidation of organic componnds that occur in microorganisms is one of the most important and basic metabolic reactions. Enzymes involved in toxic organic oxidation reactions belong to various groups of known oxidative enzymes such as peroxidases, laccases, and mixed-function oxidases. The major oxidation reactions are presented in Table 13.4. Key to detoxification of toxic organics and subsequent mineralization through oxidation include  

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Kilbane, J. J., Sulfur-specific microbial metabolism of organic compounds. Reseources, Conservation and Recycling, 1990. 3 pp. 69-79. 

Burken, J.G., Uptake and metabolism of organic compounds Green liver model. In McCutcheon, S.C. and Schnoor, J.L., editors. Phytoremediation Transformation and Control of Contaminants, John Wiley Sons, New York, pp. 59-84, 2004. 

Nitric oxide inhibits cytochrome P450 metabolism of organic compounds, resulting in the presence of increased concentrations of organic compounds that may stimulate NMDA activity. 23 ... 

Burken, J. G. 2003. Uptake and Metabolism of Organic Compounds. Green-Liver Model. Phytoremediation Tranrformation and Control of Contaminants. S.C. McCutcheon and J.L. Schnoor, eds. Indianapolis, IN John Wiley Sons, pp. 59-84. 

Burken, J. 2003. Uptake and metabolism of organic compounds green-liver model. In Phytoremediation transformation and control (McCutcheon and Schnoor Eds.) Wiley-Interscience, U.S.A., pp.59-84. 

The metabolism of nitroso compounds by microorganisms in the environment has attracted less attention than formation of the same compounds by the organisms. Tate and Alexander s... 

Horvath RS (1972) Microbial co-metabolism and the degradation of organic compounds in nature. Bacteriol Rev 36 146-155. 

Trudgill PW (1984) Microbial degradation of the alicyclic ring structural relationships and metabolic pathways. In Microbial Degradation of Organic Compounds (Ed DT Gibson), pp. 131-180. Marcel Dekker Inc, New York. 

The primary metabolism of an organic compound uses a substrate as a source of carbon and energy. For the microorganism, this substrate serves as an electron donor, which results in the growth of the microbial cell. The application of co-metabolism for bioremediation of a xenobiotic is necessary because the compound cannot serve as a source of carbon and energy due to the nature of the molecular structure, which does not induce the required catabolic enzymes. Co-metabolism has been defined as the metabolism of a compound that does not serve as a source of carbon and energy or as an essential nutrient, and can be achieved only in the presence of a primary (enzyme-inducing) substrate. 

Compared to the extensive data that have been obtained on the mutagenicity of nitro PAHs in S. typhimurium, relatively little is known about the metabolism of these compounds in this organism. Messier et al. (67) reported that incubation of 1-nitropyrene with S. typhimurium TA98 yielded 1-aminopyrene and 1-acetylaminopyrene as major and minor metabolites, respectively. The reduction of 1-nitropyrene was slow and was accompanied by a slow formation of DNA adducts. When incubations were conducted with the nitroreductase-deficient strain, TA100 F50, both the extent of 1-amino-pyrene formation and DNA binding decreased. Howard ej al. (71,115) also found reduction of 1-nitropyrene to 1-aminopyrene in strains TA98, TA1538 and ATCC 14028. 

In chemical-specific parameters used for PBPK modeling, the metabolic rate constant is crucial to the accuracy of modeling results in many cases. For some pyrethroids, hydrolysis in intestine and serum has a significant role in the metabolism of the compound in mammals besides oxidation and ester cleavage in liver, which is the most important organ for detoxification of many chemicals. 

Actinomycetes can metabolize a wide variety of organic substrates, including organic compounds that are generally not metabolized, such as phenols and steroids. They are also important in the metabolism of heterocyclic compounds such as complex nitrogen compounds and pyrimidines [42,49]. The breakdown products of their metabolites are frequently aromatic, and these metabolites are important in the formation of humic substances and soil humus [42,49]. 

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