Cloning, expression and culture optimization of gene encoding Aspergillus niger NRRL3135 phytase in Hansenula polymorpha host

Phytase is able to change phytic acid into the myo-inositiol and inorganic phosphate، so it has been used as a cereal food additive in monogastric animal’s food. The aim of this study was to eamine cloning، expression and culture optimization of gene encoding Aspergillus niger NRRL3135 phytase in Hansenula polymorpha host. In this study، in order to achieve high level production of protein، the sSequence of protein encoding fangal Aspergillus niger NRRL3135 phytase was designed according to the expression cod on usage of Hansenula polymorpha and transformation was done. The enzyme specific activity in different cultures was survived. The results in flask culture showed that the recombinant phytase production was 1185 U/L with 34. 84 U/mg specific activities in YNB-Methanol culture. Results indicate YP-methanol culture is the efficient culture to produce Aspergillus niger NRRL3135 phytase in Hansenula polymorpha as a host on industrial scale