Sulfonylureas and Thiocarbamates

Sulfonylureas are the basis of a large group of herbicides. Cytochrome P450 enzymes in Streptomyces griseolus transform the sulfonylureas by hydroxylation (Omer et al. 1990) leaving the -SO2NHCONH- part of the structure unaltered (Harder et al. 1991). 

In addition to these mechanisms, the degradation of thiocarbamates may be carried out in Rhodococcus erythropolis NI86/21 by a herbicide-inducible nonheme haloperoxidase (de Schrijver et al. 1997). 

Although it is moot whether carbon monoxide, cyanide, and thiocyanate should be included as organic compounds, brief comments on their biodegradation are summarized. 

Two mechanisms have emerged for the degradation of cyanide (Fernandez et al. 2004) and the corresponding nitriles  

Noncyanogenic fungi can degrade cyanide to formamide followed by hydrolysis by a hydratase to formate and ammonia (Dumestre et al. 1997). This pathway is also used by some bacteria (Jandyala et al. 2003). Bacteria also use a number of reactions for the detoxification of cyanide, including monooxygenation to COj and ammonia (Wang et al. 1996). 

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