Studies on the Overexpression of Alkali-tolerant Xylanase in Bacillus Pumilus

The xylanase-encoding gene xynA and it's promoter were cloned from Bacillus pumilus BP51. The gene was inserted in Bacillus expression vector pWG03 which was modificated Bacillus expression one. The recombinant plasmid pWGXYN was transformed into B.pumilus BP4756 by protoplast transformation method and the recombinant B.pumilus BPSDBY was obtained. The xynA in recombinant strain was over expressed and the xylanase was secreted into medium. The xylanase activity produced by recombinant BPSDBY had increased about 20 times as compared with the host strain BP4756. At some time the enzymology properties of the recombinant xylanase were also studied.