Compared D-amino acid oxidase expression in different Pichia pastoris host strains.
- Author:
Mei-Qing FENG
1
;
Hai HUANG
;
Xun-Long SHI
;
Zhi-Liang YU
;
Zhong-Yi YUAN
;
Pei ZHOU
Author Information
1. Fudan University, Shanghai 200032, China.
- Publication Type:Journal Article
- MeSH:
D-Amino-Acid Oxidase;
genetics;
Fermentation;
Methanol;
metabolism;
Phenylalanine;
metabolism;
Pichia;
genetics;
Polymerase Chain Reaction
- From:
Chinese Journal of Biotechnology
2004;20(4):572-577
- CountryChina
- Language:Chinese
-
Abstract:
To compare the DAAO expression level in different Pichia pastoris host strains, the gene encoding DAAO from Trigonopsis variabilis was cloned into plasmid pPIC3.5k and then transformed into P. pastoris GS115 and KM71 respectively. The positive transformants PDK13 (MutS) and PD27 (Mut+) were obtained by PCR analysis. Their optimal and different expression conditions were investigated. To compare with PD27, PDK13 was determined to poss a slower consumption of methanol, a longer induction time, a lower oxygen request and apparently higher expression of DAAO. The highest expression levels were reached up to 2700, 2500 IU/L in shaking flask and 10140, 8463.5 IU/L in fermentor respectively. The over-expression of DAAO can meet its large demand for production of 7-ACA, alpha-keto acid and L-amino acid. In addition, the phenylpyruvate and L-phenylalanine were obtained by crude DAAO reacting with DL-phenylalanine at 37 degrees C for 3h.
