Fig. 6

Biochemical characterization of MsAA

(A) pH dependency of hydrolytic activity. Reaction conditions: 15 mM acetyl-alanine at 30 °C reaction temperature. The following buffers were used at 100 mM: Na-acetate for pH 4.0 and 5.0, Tris-HCl for pH 6.0–9.0, Na-borate for pH 9.0–13.0. (B) pH dependency of stability after 24 h and (C) after 5 d at 30 °C. Buffers and corresponding symbols used are identical to the pH activity optimum. Residual activity was determined with the standard assay conditions and indicated as percental values. (D) Temperature dependency on hydrolytic activity. Reaction conditions were 15 mM acetyl-alanine in 100 mM Tris-HCl pH 7.0 at various reaction temperatures. (E) Thermal stability after 1 h, 24 h and 5 days incubation at various temperatures in 100 mM Tris-HCl buffer pH 7.0. (F) Thermal shift assay. Thermal denaturation of MsAA was followed via fluorescence measurement of SYPRO Orange. All reactions were conducted in triplicates