title: Azo reduction of trypan blue to a known carcinogen by a cell-free extract of a human intestinal anaerobe.
abstract: The azo reductase activity of a cell-free extract of Fusobacterium sp. 2 is characterized using trypan blue as a substrate. Either chemical reduction of this dye with sodium hydrosulfite or reduction by the cell-free extract produces a mutagenic product, o-tolidine. The o-tolidine is mutagenic in the Ames Salmonella/mammalian-microsome mutagenicity test when activated by a rat liver S9 preparation.
mesh_terms: D001560:Benzidines / Q000378:metabolism; D002273:Carcinogens; D005673:Fusobacterium / Q000201:enzymology*; D005821:Genetic Techniques; D006801:Humans; D007422:Intestines / Q000382:microbiology; D009153:Mutagens; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism*; D014343:Trypan Blue / Q000378:metabolism*; D004124:p-Dimethylaminoazobenzene
chemical_list: D001560:Benzidines; D002273:Carcinogens; D009153:Mutagens; C009501:2-tolidine; D004124:p-Dimethylaminoazobenzene; D009247:NADH, NADPH Oxidoreductases; D014343:Trypan Blue