Biotransformation reactions glutathione conjugation

With compounds of sufficient reactivity, these reactions can also occur nonenzymatically. Once formed, glutathione conjugates (GS-R) are seldom excreted as such, but usually undergo further biotransformation. Cleavage of the glutamyl moiety by glutamyl transpeptidase and of the cysteinyl... 

Cysteine conjugates and the twin-ion technique. In addition to studies of glutathione conjugates, we have utilized the twin--ion technique to study reaction mechanisms in reactive metabolite formation from acetylhydrazine and isopropylhydrazine. This technique has proven to be a useful tool when applied to biotransformation studies. Hammar and Holmstedt (15) used the naturally occurring isotopic doublet of chlorine to study the metabolism of chlorpromazine. Morfin et al. (16) were the first to use stable isotope standards in studies of the pathways of testosterone... 

Different enzymatic reactions that occur during the metabolism of chemicals have been well categorized. The biotransformation and conjugation reactions may lead to either the detoxication of the toxicant and the excretion of its metabolites, or to the activation of the toxicant into more reactive intermediates. These may, in turn, react with glutathione, or tissue proteins, or nucleic acids (e.g., RNA, DNA) and undergo different metabolic reactions. 

---