D-Amino acid aminotransferase (D-AAT) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme. n-AAT from thermophilic. Bacillus sp. YM-1 was inactivated by ultraviolet irradiation. The activity was restored by the addition of PLP and showed a linear correlation with respect to PLP concentrations in the range of 10-40 nM. (C) 2014, The Society for Biotechnology, Japan. All rights reserved.