Stereoisomers of glutathione: preparation and enzymatic reactivities.
We synthesized a series of stereoisomers of glutathione (GSH) and glutathione disulfide (GSSG) by the solid-phase method. These peptides were used to examine their reactivities with enzymes acting on glutathione. The glutathione reductase of yeast acted only on LL-GSSG. Glutathione S-transferase catalyzed the conjugation of 1-chloro-2,4-dinitrobenzene with LL-GSH and DL-GSH (Km (mM): for LL-GSH, 0.035; and for DL-GSH, 0.62), but the DD- and LD-diastereomers were inert. gamma-Glutamyl transpeptidase catalyzed the transfer of gamma-glutamyl moiety of LL-GSH and DL-GSH to taurine forming gamma-glutamyl taurine and cysteinyl taurine (Km (mM): for LL-GSH, 0.336; and for DL-GSH, 0.628), but the other diastereomers were not the substrates. The occurrence of L-cysteinyl residue in the tripeptides is required for the glutathione analogue to be a substrate of the enzymes.
Oikawa
T
T
Department of Biotechnology, Faculty of Engineering, Kansai University, Osaka, Japan.
Yamauchi
T
T
Kumagai
H
H
Soda
K
K
D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D005978:Glutathione / Q000138:chemical synthesis / Q000737:chemistry*; D019803:Glutathione Disulfide / Q000138:chemical synthesis / Q000737:chemistry*; D005980:Glutathione Reductase / Q000737:chemistry*; D005982:Glutathione Transferase / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013237:Stereoisomerism; D005723:gamma-Glutamyltransferase / Q000737:chemistry*
D005980:Glutathione Reductase; D005723:gamma-Glutamyltransferase; D005982:Glutathione Transferase; D005978:Glutathione; D019803:Glutathione Disulfide