Fig. 5From: Exploring the contributions of two glutamate decarboxylase isozymes in Lactobacillus brevis to acid resistance and γ-aminobutyric acid productionCell-bound GAD activities of recombinant L. brevis strains. Cells were collected at exponential-phase (24 h). One unit (U) of GAD activity was defined as the amount of cells that produced 1 µmol/L of GABA in 1 min at pH 4.8. The specific activity of GAD was defined as U/mg DCWBack to article page