γ-L-Glutamyl-L-alanine, composed of gamma-glutamate and alanine, is a proteolytic breakdown product of larger proteins. γ-L-Glutamyl-L-alanine is a natural substrate of the γ-Glutamylcyclotransferase. γ-L-Glutamyl-L-alanine is a positive modulator of calcium-sensing receptor (CaR) function[1][2][3][4].