Strain improvement of Pichia kudriavzevii TY13 for raised phytase production and reduced phosphate repression
Journal article, 2017

In this work, we present the development and characterization of a strain of Pichia kudriavzevii (TY1322), with highly improved phytate-degrading capacity. The mutant strain TY1322 shows a biomass-specific phytate degradation of 1.26 mmol g−1 h−1 after 8 h of cultivation in a high-phosphate medium, which is about 8 times higher compared with the wild-type strain. Strain TY1322 was able to grow at low pH (pH 2), at high temperature (46°C) and in the presence of ox bile (2% w/v), indicating this strain's ability to survive passage through the gastrointestinal tract. The purified phytase showed two pH optima, at pH 3.5 and 5.5, and one temperature optimum at 55°C. The lower pH optimum of 3.5 matches the reported pH of the pig stomach, meaning that TY1322 and/or its phytase is highly suitable for use in feed production. Furthermore, P. kudriavzevii TY1322 tolerates ethanol up to 6% (v/v) and shows high osmotic stress tolerance. Owing to the phenotypic characteristics and non-genetically modified organisms nature of TY1322, this strain show great potential for future uses in (i) cereal fermentations for increased mineral bioavailability, and (ii) feed production to increase the phosphate bioavailability for monogastric animals to reduce the need for artificial phosphate fortification.

Author

Linnea Qvirist

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Egor Vorontsov

University of Gothenburg

Jenny Veide Vilg

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Thomas Andlid

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Microbial Biotechnology

1751-7907 (ISSN)

Vol. 10 2 341-353

Subject Categories

Biological Sciences

Areas of Advance

Life Science Engineering (2010-2018)

DOI

10.1111/1751-7915.12427

More information

Latest update

2/21/2018