Colon nitroreductase

Redox reaetions and hydrolysis are the predominant metabolie eonversions triggered by the intestinal microflora. The main reductive enzymes produeed by the intestinal mieroflora are nitroreductase, deaminase, urea dehydroxylase, and azoreduetase the hydrolytic enzymes are P-glucoronidase, P-xylosidase, P-galaetosidase, and a-L-arabinosidase. Studies conducted by Macfarlane and co-workers have shown that proteolysis ean also happen in the colon [31]. More recent findings by this group indieate that bacterial fermentation of proteins in humans could account for 17% of... 

The metabolic transformation of many drugs is catalysed by various enzyme of the intestinal microflora. The anaerobic microflora and colon are rich in reductases which may be responsible for a significant proportion of the azoreductase and nitroreductase activity. The enzymes and other factors that may produce change in the nature of intestinal microflora might also produce changes in the metabolism pattern of the drugs. 

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