Methyl microbial process

Microbial processes can also detoxify mercury ions and organic compounds by reducing the mercury to the elemental form, which is volatile (86). This certainly reduces the environmental impact of compounds such as methyl-mercury, however, such a bioprocess would have to include a mercury capture system before it could be exploited on a large scale with public support. 

The synthesis of oral taxane 40 also reqnired 4,10-dideacetyl baccatin 43 (Fignre 16.11C) as starting material for the chemical synthesis of the C-4 methyl-carbonate derivative of 10-deacetyl baccatin III 44. A microbial process was developed for deacetylation of 10-deacetylbaccatin III 35 to 4,10-dideacetylbaccatin III 43 nsing a Rhodococcus sp. SC 162949 isolated from soil using culture enrichment techniqnes [69]. Chemically, 43 is converted to 44, a C-4 methylcarbonate derivative 10 deactylbacattin III. 

Cheese flavor. C. f. is formed from milk fat, milk protein, lactose during the maturation of cheese mainly through enzymatic and microbial processes. Quantitative and, sometimes, qualitative differences are responsible for the diversity of cheese flavors. Typical aroma substances are the free C4-C,2 fatty acids, C7, C and C, 2-alkanones (also in Roquefort cheese), the butter aroma substances acetoin, 2,3-butanedione, and 5- alkanolides, (-)-(R)-l-octen-3-ol (fungus note in Camembert), 4-alkanolides and alkylpyrazines with nut-like nuances, indole, skatole, and phenols with stable-like odors, as well as numerous sulfur compounds such as methional, methyl mercaptan (moldy, coal-like), dimethyl sulfide and dialkyl polysulfides with, in part, onion- and garlic-like nuances. Furaneol" and homofuraneol (see hydroxyfura-nones) are responsible for the sweetish odor of Em-mental cheese. 

There are two pathways of degradation of DMNA by microbial enzymes and by microsomal P-450. One is denitrosation and the other demethylation. Denitrosation is a mflin microbial process for removal of DMNA from the environment, although its degradation through demethylation also takes place by a methanotroph. The reaction catalyzed by microsomal P-450 can couple with the methylation of DNA, a central paradigm for initiation of carcinogenesis. 

Although the entry of MeHg into the base of the food web and its subsequent transfer in the lowest trophic levels are poorly understood, it is evident that the concentration of MeHg in all trophic levels is strongly correlated with its supply from methylating environments. In fish, for example, much of the modem spatial variation in mercury concentrations (within a given trophic level) can be attributed to variation in factors and processes that affect the microbial production of MeHg and its entry into oxic waters. 

Biopract provides technological products and processes for industry, agriculture, and environment. They not only produce technical enzyme preparations but also develop enzymes for applications in agriculture, food, and textile industry as well as in environmental technologies. On the later, bioremediation has been an area of service delivery from Biopract. Their activities regards microbial preparations for the bioremediation of organic contaminants (mineral oil (MKW), polycyclic aromatic hydrocarbons (PAH), benzene, toluene, ethylbenzene, xylene (BTEX), methyl-tert-butyl ether (MTBE), volatile organic hydrocarbons (VOC), and dimethyl sulfoxide (DMSO)). 

The classic studies by Challenger (127-129) on microbial methyla-tion of arsenic still provide the basis of our understanding of these processes. Although Challenger s work focused on mycological methyla-tions (he mistakenly believed that bacteria did not methylate arsenic), the scheme he proposed is applicable to other biological systems as well. It is briefly discussed here, together with the confirmatory studies of Cullen and co-workers. 

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