Glutathione biosynthesis and the cystine cysteine redox cycle as driven Download Scientific Diagram NAC N Acetyl L Cysteine Figure 1 from Depletion of Glutathione during Oxidative Stress and Efficacy of N Acetyl Cysteine: An Old Drug with New Approaches Semantic Scholar Sulfur metabolism under stress: Oxidized glutathione inhibits methionine biosynthesis by destabilizing the enzyme cystathionine < em> synthase