SDS-PAGE analysis of recombinant S. plymuthica AS9 PalI and its variants expressed in E. coli BL21(DE3).

(A) Lane M, molecular weight markers; Lane 1, culture supernatant of the wild-type enzyme; Sucrose isomerase is indicated by the black arrow. (B) Lane M, molecular weight markers; Lane 1, purified wild-type enzyme; Lane 2, purified E175N; Lane 3, purified K576D; Lane 3, purified E175N/K576D.