Mutagens metabolism, tryptophan

Metabolism of Comutagens and Mutagens Produced from Tryptophan Pyrolysis... 

The alternative explanation must involve the MFO system. The possible mechanism for the inhibitory effect or enhancement effect of Norharman upon covalent DNA binding and mutagenicity must be the results of the net balancing of substrate inhibition and membrane fluidization of the microsomal membrane or of the lipid vesicles in the reconstituted MFO system. A schematic pathway of the metabolism of these tryptophan pyrolysis products is postulated as shown in Figure 8. 

Significant mutagenic activity was detected with pyrolysates of most of the materials tested. The highest mutagenic activity was observed with pyrolysate of a tryptophan-containing peptide. The pyrolysates required a liver microsomal portion, representative of mammalian metabolism, for the detection of mutagens. 

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