Partial purification and some biochemical properties of neonatal rat cutaneous glutathione S-transferases

Abstract

1. 1. Previous studies have demonstrated the presence of glutathione S-transferases in the skin of rodents and humans. This study represents the first attempt to purify cytosolic glutathione S-transferases from skin of 3-day-old rats.2. 2. A partial purification of the enzyme was achieved by a two-step procedure: affinity chromatography followed by HPLC. Two peaks, one major (P-1) and one minor (P-2), were resolved by HPLC containing about 82% and 10% of the recovered activity, respectively.3. 3. The major form exhibited an overall purification of about 2270-fold with a specific activity of about 73 [mu]moles/min/mg protein towards 1-chloro-2,4-dinitrobenzene.4. 4. The kinetic data for P-1 yielded mean Km values of 2.39 mM for 1-chloro-2,4-dinitrobenzene and 0.72 mM for reduced glutathione, while the respective average Vmax values were found to be 212 and 101 [mu]moles/min/mg protein.5. 5. Significantly inhibition of enzyme activity was noted in the presence of 0.2 mM HgCl2, 0.63 [mu]M 1.2-naphthoquinone, 1.0 [mu]M triphenyltin chloride, and 12.5 [mu]M 17[beta]-estradiol-3-sulfate.