DNA fragments analysis by ethidium bromide stained 1% agarose gel. A, PCR amplified type II pullulanase gene. Lane M, Kilobase DNA marker; Lane 1, 3.1 kbp PCR amplified apu gene. B, Analysis of recombinant pET101-APU plasmid. Lane M, standard; Lane 1, pET101-APU plasmid cut with HindIII restriction enzyme.