title: Glutathiyl radical as an intermediate in glutathione nitrosation.
abstract: Nitrosation of thiols is thought to be mediated by dinitrogen trioxide (N(2)O(3)) or by nitrogen dioxide radical (()NO(2)). A kinetic study of glutathione (GSH) nitrosation by NO donors in aerated buffered solutions was undertaken. S-nitrosoglutathione (GSNO) formation was assessed spectrophotometrically and by chemiluminescence. The results suggest an increase in the rate of GSNO formation with an increase in GSH with a half-maximum constant EC(50) that depends on NO concentration. Our observed increase in EC(50) with NO concentration suggests a significant contribution of ()NO(2)-mediated nitrosation with the glutathiyl radical as an intermediate in the production of GSNO.
authors.affiliation: Department of Biomedical Engineering, Florida International University, Miami, FL 33174, USA.
authors.forename: Kumpal
authors.initials: K
authors.lastname: Madrasi
authors.forename: Mahesh S
authors.initials: MS
authors.lastname: Joshi
authors.forename: Tushar
authors.initials: T
authors.lastname: Gadkari
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Kavallieratos
authors.forename: Nikolaos M
authors.initials: NM
authors.lastname: Tsoukias
mesh_terms: D002384:Catalysis; D005978:Glutathione / Q000737:chemistry* / Q000378:metabolism*; D007700:Kinetics; D009569:Nitric Oxide / Q000032:analysis / Q000737:chemistry*; D009585:Nitrogen Dioxide / Q000737:chemistry*; D015538:Nitrosation; D026422:S-Nitrosoglutathione / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D013438:Sulfhydryl Compounds; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione; D005978:Glutathione; D009585:Nitrogen Dioxide