incubation of normal human skin fibroblasts or fibroblasts derived from patients with erythrocyte deficiency of gamma-glutamylcysteine synthetase ( gamma-glutamylcysteine synthetase-deficient ) in culture medium containing l- [ 35s ] cystine resulted in incorporation of radioactivity into protein , cysteine , and glutathione , gamma-glutamylcysteine synthetase-deficient fibroblasts synthesized glutathione from [ 35s ] cystine at 30 % the rate of normal cells and contained 30 % the normal amount of glutathione .
C0016030
fibroblasts
C0007634
the