Synthesis of vitamin K2 by isopentenyl transferase NovA in Pichia pastoris Gpn12.
- Author:
Xihua WU
1
;
Zhemin LI
1
;
Hui LIU
1
;
Peng WANG
1
;
Li WANG
1
;
Xue FANG
1
;
Xiaowen SUN
1
;
Wenfeng NI
1
;
Qiang YANG
1
;
Zhiming ZHENG
1
;
Genhai ZHAO
1
Author Information
- Publication Type:Journal Article
- Keywords: Pichia pastoris; optimization; vitamin K2; whole-cell catalysis
- From: Chinese Journal of Biotechnology 2018;34(1):140-148
- CountryChina
- Language:Chinese
- Abstract: The effect of methanol addition on the heterologous expression of isoprenyl transferase NovQ was studied in Pichia pastoris Gpn12, with menadione and isopentenol as precursors to catalyze vitamin K2 (MK-3) synthesis. The expression of NovQ increased by 36% when 2% methanol was added every 24 h. The influence of initial pH, temperature, methanol addition, precursors (menadione, isopentenol) addition, catalytic time and cetyltrimethyl-ammonium bromide (CTAB) addition were explored in the P. pastoris whole-cell catalytic synthesis process of MK-3 in shaking flask. Three significant factors were then studied by response surface method. The optimal catalytic conditions obtained were as follows: catalytic temperature 31.56 ℃, menadione 295.54 mg/L, catalytic time 15.87 h. Consistent with the response surface prediction results, the optimized yield of MK-3 reached 98.47 mg/L in shaking flask, 35% higher than that of the control group. On this basis, the production in a 30-L fermenter reached 189.67 mg/L when the cell catalyst of 220 g/L (dry weight) was used to catalyze the synthesis for 24 h. This method laid the foundation for the large-scale production of MK-3 by P. pastoris Gpn12.
