来源： Lett. Appl. Microbiol.日期： 2015-01-29
Aims: Dammarenediol production by an engineered yeast Saccharomyces cerevisiae was investigated.
Methods and Results: A dammarenediol-producing engineered yeast was constructed by heterologous expression of the dammarenediol synthase gene from Panax ginseng hairy roots through RT-PCR. Fermentation was carried out in a 5-L GRJY-bioreactor with an inoculum size of 1% v/v at 30 degrees C. Dammarenediol detection was performed with silica gel chromatography and HPLC. Determination of dammarenediol synthase activity subcellular distribution was carried out by surveying the enzyme activity in microsomes, lipid particles and total yeast homogenate. When cultured under aerobic conditions, the engineered yeast could produce dammarenediol up to 250 mu g l(-1). However, when an anaerobic shift strategy was employed, dammarenediol accumulated at a level as twice as that under aerobic condition. The dammarenediol synthase and dammarenediol were mainly localized in lipid particles.