l-cysteine peptide is glutathione Critical Roles of the Cysteine–Glutathione Axis in the Production of γ-Glutamyl Peptides in the Nervous System What is Glutathione? – GoldBio
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Qiu Y, Tong S, Zhang L, Sakurai Y, Myers DR, Hong L, Lam WA, Bao G
, Cao S

Interestingly, the inhibition by a semi-selective orthosteric antagonist LY341495 at concentrations that only inhibit mGluR2 inhibited the receptor partially, whereas complete inhibition is achieved with a concentration that inhibits both mGluR2 and mGluR4 (139)

11C), implying minimal structural disturbance to the protein

Lewis, K
