“…Analyses of the isotopic distributions of 2H and/or 34S in the bound serine, cysteine, and methionine were performed by GC-MS of the N-trifluoroacetyl n-butyl ester derivative of methionine, the N,O-trifluoroacetyl n-butyl ester derivative of serine, and the S-methyl-N-trifluoroacetyl n-butyl ester derivative of cysteine. (Brueggeman et al, 1962;Wiebers & Garner, 1967); (d) cysteine desulfhydrase (Fromageot, 1951;Ohkishi et al, 1981); (e) enzymatic or nonenzymatic reductive cleavage by intracellular thiols, Le., glutathione (Flavin, 1962); (f) 0-cystathionase (Flavin & Slaughter, 1964;Delavier-Klutchko & Flavin, 1965b); (g) decomposition into sulfane sulfur and cysteine (Flavin, 1962); (h) transamination (Rudman & Meister, 1953); (i) mercaptopyruvate sulfurtransferase (Meister et al, 1954;Vachek & Wood, 1972); 6) reduction of sulfane sulfur [So] to sulfide catalyzed by sulfane reductase. The reaction could proceed with or without the involvement of rhodanese (Westley, 1981).…”