High impact information on S-Methylglutathione

• The same binding in the presence of S-methylglutathione or protoporphyrin IX shows a decreased reaction rate with respect to the reaction in the absence of inhibitors, indicating that the thiols are in proximity of both the glutathione and the porphyrin binding sites [1].
• The heterodimer is also formed in the presence of S-methylglutathione, but no 1-Cys Prx activity is found under these conditions [2].
• The acylated product is stable for more than 24 h at pH 7 and 25 degrees C. The modification is reversible in the presence of excess glutathione, but the labeled protein can be protected by adding S-methylglutathione [3].
• All wild-type enzymes and H107S chimera have nearly identical equilibrium constants for formation of enzyme-GSH complexes (Kd values of 1-2 x 10(-)6 M); however, KmGSH and Ki values for S-methylglutathione inhibition determined by steady-state kinetics are nearly 100-fold higher [4].
• Subsequent experiments indicated that the inhibitory effects of both glutathione and S-methylglutathione on thiopurine methyltransferase may be due to their acidic natures, changing the reaction mixture pH away from the optimal range for the enzyme [5].

Anatomical context of S-Methylglutathione

• A second HPLC phenotyping routine procedure based on the formation of S-methylglutathione from methyl chloride in erythrocyte lysate incubations (Müller et al. 2001, Arch Toxicol 74:760-767) was established and validated by genotyping [6].

Analytical, diagnostic and therapeutic context of S-Methylglutathione

• We have developed an HPLC assay for formation of S-methylglutathione and S-ethylglutathione that is applicable to measuring enzyme activity toward a variety of xenobiotic substrates [7].
• High-performance liquid chromatography/fluorescence detection of S-methylglutathione formed by glutathione-S-transferase T1 in vitro [8].
• Simultaneously, the production of S-methylglutathione was determined by thin layer chromatography [9].

References