Open AccessCell‐surface phytase on Pichia pastoris cell wall offers great potential as a feed supplement
Author(s) -
Harnpicharnchai Piyanun,
Sornlake Warasirin,
Tang Kittapong,
Eurwilaichitr Lily,
Tanapongpipat Sutipa
Publication year - 2010
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2009.01811.x
Subject(s) - phytase , pichia pastoris , yeast , biochemistry , extracellular , biology , cell , chemistry , enzyme , recombinant dna , gene
Cell‐surface expression of phytase allows the enzyme to be expressed and anchored on the cell surface of Pichia pastoris . This avoids tedious downstream processes such as purification and separation involved with extracellular expression. In addition, yeast cells with anchored proteins can be used as a whole‐cell biocatalyst with high value added. In this work, the phytase was expressed on the cell surface of P. pastoris with a glycosylphosphatidylinositol anchoring system. The recombinant phytase was shown to be located at the cell surface. The cell‐surface phytase exhibited high activity with an optimal temperature at 50–55 °C and two optimal pH peaks of 3 and 5.5. The surface‐displayed phytase also exhibited similar pH stability and pepsin resistance to the native and secreted phytase. In vitro digestibility test showed that P. pastoris containing cell‐surface phytase released phosphorus from feedstuff at a level similar to secreted phytase. Yeast cells expressing phytase also provide additional nutrients, especially biotin and niacin. Thus, P. pastoris with phytase displayed on its surface has a great potential as a whole‐cell supplement to animal feed.