A novel purification procedure of L-lysine 6-aminotransferase from Flavobacterium lutescence

A new method for the purification of L-lysine 6-aminotransferase (L-lysine: 2-oxoglutarate 6-aminotransferase, EC 2.6.1.36) was devised, in which affinity chromatography with L-lysylacetamidododecyl-Sepharose 6B, the most effective affinity adsorbent, was substituted for the heat treatment. The yield of the enzyme with the present procedure was approx. twice as high as that with the previous procedure (Soda, K. and Misono, H. (1968) Biochemistry 7, 4110-4119). The enzyme purified by this method was activated 2-fold by heat treatment (65 degrees C for 5 min). The enzyme has absorption maxima at 340 and 415 nm, derived from the bound pyridoxal 5'-phosphate, which are identical with those of the enzyme obtained with the procedure including heat treatment. These results rule out the possibility that the formation of the 340-nm pyridoxal 5'-phosphate of the enzyme is an artifact of heat treatment.