Catabolism of extracellular glutathione supplies cysteine to support tumours Nature Glutamylcysteine SynthetaseGlutathione Synthetase: Domain Structure and Identification of Residues Important in Substrate and Glutathione Binding Biochemistry Kokumi! If you want a whole picture on umami, there's the core concept of glutamate, then a second level of umami boosting from ribonucleotides like IMP. There's a third layer that's not Glutathione Gsh Antioxidant Plants Animals Fungi Stock Illustration 1320541694 Shutterstock L Glutathione vs. Glutathione: What's the Difference? Invigor Medical