Comparison of biochemical properties of recombinant phytase expression in the favorable methylotrophic platforms of Pichia pastoris and Hansenula polymorpha

Document Type: Original Research Papers

Authors

1 Department of Plant Biotechnology, National Institute of Genetic Engineering and Biotechnology,,Tehran,IRAN(NIGEB)

2 Nanobiotechnology Engineering Laboratory , Shahid Beheshti University, ,Faculty of Energy and New Technologies,Tehran,IRAN

3 Nanobiotechnology Engineering Laboratory,Faculty of Energy and New Technologies,Shahid Beheshti University, ,Tehran,IRAN

4 Nanobiotechnology Engineering Laboratory ,Faculty of Energy and New Technologies,Shahid Beheshti University,Tehran,IRAN

Abstract

Phytic acid is the dominant form of phosphorous in plant seeds. However, phytic acid cannot be
utilized by animals and causes them serious phosphate deficiency. Utilization of phytase as an
animal feed additive can affect liberation of phosphor and its mineral availability. In this study,
heterologous expression of the A. niger phyA gene was investigated in the methylotrophic yeasts
P. pastoris and H.polymorpha and its expressed active recombinant phytase biochemical and
biophysical properties were studies and compared to native A.niger phytase. The phyA gene
sequence of A.niger was designed and expression of synthetic genes was highly successfully in
active form in both yeast hosts. Size of the secreted recombinant phytases, due to heavy
glycosylation, varied from 50 to 65 KDa. Expressed extracellular recombinant phytase samples
were purified and biochemical tests on properties demonstrated that both recombinant phytase
samples had similar pH profiles with pH optima determinations of pH 2.5, pH.5.5 as acid
phosphatase and optimum temperature of 60 and 50 °C respectively in P. pastoris and H.
polymorpha. This study concludes that recombinant P. pastoris and H. polymorpha phytases could fulfil a
series of predefined industrial quality criteria for application as animal feed supplement.

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