Coomassie brilliant blue stained SDS-PAGE demonstrating the production of type II pullulanase. A, Lane M, protein marker; Lane 1, cells carrying pET101 vector; Lane 2, cells carrying pET101-APU plasmid; Lane 3, soluble fraction of the sample in lane 2; Lane 4, soluble fraction after heat treatment of sample in lane 3; Lane 5, purified recombinant type II pullulanase. B, Activity of purified type II pullulanase.