Detail of "6367-98-2"

Reference

Role for an episulfonium ion in S-(2-chloroethyl)-DL-cysteine-induced cytotoxicity and its reaction with glutathione

Role for an episulfonium ion in S-(2-chloroethyl)-DL-cysteine-induced cytotoxicity and its reaction with glutathione. Webb, William W.; Elfarra, Adnan A.; Webster, Kathy D.; Thom, Rebecca E.; Anders, M.Chemicals with cas numbers 108031-84-1 and 107940-95-4 also play role. W. (Sch. Med. Dent., Univ. Rochester, Rochester, NY 14642, USA). Biochemistry, 26(11), 3017-23 (English) 1987. CODEN: BICHAW. ISSN: 0006-2960. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) S-(2-Chloroethyl)-DL-cysteine (CEC) [98069-36-4] caused a time- and concn.-dependent loss of isolated rat hepatocytes viability. Depletion of intracellular glutathione [70-18-8] concns. (>70%) and inhibition of microsomal Ca2+ transport and Ca2+-activated ATPase [9000-83-3] activity preceded the loss of cell viability, and initiation of lipid peroxidn. paralleled the loss of viability. The depletion of glutathione concns. was partially attributable to a reaction between glutathione and CEC to form S-[2-(DL-cysteinyl)ethyl]glutathione [107940-95-4], which was identified by NMR and mass spectrometry. N-Acetyl-L-cysteine, vitamin E, and N,N'-diphenyl-p-phenylenediamine protected against the loss of cell viability. N,N'-Diphenyl-p-phenylenediamine inhibited CEC-initiated lipid peroxidn. but did not protect against cell death at 4 h, indicating that lipid peroxidn. was not the cause of cell death. The analogs S-ethyl-L-cysteine [2629-59-6], S-(3-chloropropyl)-DL-cysteine [97142-18-2], and S-(2-hydroxyethyl)-L-cysteine [6367-98-2], which cannot form an episulfonium ion, were not cytotoxic, thus demonstrating a role for an episulfonium ion in the cytotoxicity assocd. with exposure to CEC and, possibly, 1,2-dichloroethane. An alteration in Ca2+ homeostasis and the generation of an electrophilic intermediate may be involved in the mechanism of cell death. .

S-(N-Methylthiocarbamoyl)-L-cysteine, a suicide substrate of L-methionine g-lyase

S-(N-Methylthiocarbamoyl)-L-cysteine, a suicide substrate of L-methionine g-lyase. Esaki, Nobuyoshi; Kimura, Tomio; Goto, Joji; Nakayama, Toru; Tanaka, Hidehiko; Soda, Kenji (Inst. Chem. Res., Kyoto Univ., Uji 611, Japan). Biochim. Biophys. Acta, 785(1-2), 54-60 (English) 1984. CODEN: BBACAQ. ISSN: 0006-3002.Several reagents with their cas registry numbers 6367-98-2 and 60-24-2 are used here. DOCUMENT TYPE: Journal CA Section: 7 (Enzymes) S-(N-Methylthiocarbamoyl)-L-cysteine (I) functions as a suicide substrate for L-methionine g-lyase (EC 4.4.1.11) (II) from Pseudomonas putida; it undergoes the a,b-elimination and causes time-dependent inactivation. The partition ratio is ~800/inactivation event. However, II catalyzes a b-replacement reaction producing S-(b-hydroxyethyl)-L-cysteine in the presence of b-mercaptoethanol (50 mM), but is not inactivated. Thus, b-mercaptoethanol probably reacts with an inactivating species derived enzymically from I instead of a nucleophilic amino acid residue at the active site that is modified with I in the absence of b-mercaptoethanol. When II was incubated with [1,2,3-U-14C]I, the tetrameric enzyme was labeled with 4 mol of 14C-labeled inactivator. II inactivated with [14C]I slowly regained ~50% of the original enzyme activity with a concomitant loss of ~50% of the radioactivity incorporated after dialysis. The results indicate that II has 2 different residues modified with I at the active site, and that 1 of the 2 resulting adducts is unstable and the other stable to solvolysis. II is inactivated similarly by S-(N-methylcarbamoyl)-L-cysteine. The amino acid also partitions between a,b-elimination and suicidal inactivation. However, S-ethyl-L-cysteine does not inactivate I. This is probably due to protection of I by ethanethiol produced from S-ethyl-L-cysteine, as obsd. for b-mercaptoethanol added to the reaction mixt. .