FIG. 3.

DapL activity (A) and heat stability (B) of MJ1391. (A) The DapL assay was performed at 70°C for 0 to 60 min before termination and measurement of the product glutamate. (B) The temperature stabilities of MJ1391 and the substrates α-KG and ll-DAP were examined by preincubation of the MJ1391 protein (open bars), the substrates (gray bars), or the protein and the substrates (incubated separately) (black bars) at 70 to 100°C in Tris-HCl buffer (pH 8.5) for 30 min before the DapL activity assay was performed at 70°C. One hundred percent activity was defined as the activity that was observed without preincubation (0.30 μmol min⁻¹ mg of protein⁻¹). The error bars indicate the standard deviations of three assays.