Evolutionary engineering of Phaffia rhodozyma for astaxanthin-overproducing strain  

作　　者：Jixian GONG Nan DUAN Xueming ZHAO 

机构地区：[1]School of Textiles,Tianjin Polytechnic University,Tianjin 300160,China [2]School of Chemical Engineering and Technology,Tianjin University,Tianjin 300072,China

出　　处：《Frontiers of Chemical Science and Engineering》2012年第2期174-178,共5页化学科学与工程前沿（英文版）

基　　金：Acknowledgements This work was supported by the National Basic Research Program of China （973） （Grant No. 2007CB707802）, and the National Natural Science Foundation of China （Grant Nos. 20806055, 20875068）.

摘　　要：Evolutionary engineering is a novel whole- genome wide engineering strategy inspired by natural evolution for strain improvement. Astaxanthin has been widely used in cosmetics, pharmaceutical and health care food due to its capability of quenching active oxygen. Strain improvement ofPhaffia rhodozyma, one of the main sources for natural astaxanthin, is of commercial interest for astaxanthin production. In this study a selection procedure was developed for adaptive evolution of P. rhodozyma strains under endogenetic selective pressure induced by additive in environmental niches. Six agents, which can induce active oxygen in cells, were added to the culture medium respectively to produce selective pressure in process of evolution. The initial strain, P. rhodozyma AS2-1557, was mutagenized to acquire the initial strain population, which was then cultivated for 550 h at selective pressure and the culture was transferred every 48h. Finally, six evolved strains were selected after 150 generations of evolution. The evolved strains produced up to 48.2% more astaxanthin than the initial strain. Our procedure may provide a promising alternative for improvement of highproduction strain.Evolutionary engineering is a novel whole- genome wide engineering strategy inspired by natural evolution for strain improvement. Astaxanthin has been widely used in cosmetics, pharmaceutical and health care food due to its capability of quenching active oxygen. Strain improvement ofPhaffia rhodozyma, one of the main sources for natural astaxanthin, is of commercial interest for astaxanthin production. In this study a selection procedure was developed for adaptive evolution of P. rhodozyma strains under endogenetic selective pressure induced by additive in environmental niches. Six agents, which can induce active oxygen in cells, were added to the culture medium respectively to produce selective pressure in process of evolution. The initial strain, P. rhodozyma AS2-1557, was mutagenized to acquire the initial strain population, which was then cultivated for 550 h at selective pressure and the culture was transferred every 48h. Finally, six evolved strains were selected after 150 generations of evolution. The evolved strains produced up to 48.2% more astaxanthin than the initial strain. Our procedure may provide a promising alternative for improvement of highproduction strain.

关 键 词：evolutionary engineering ASTAXANTHIN strain improvement 

分 类 号：Q111[生物学—普通生物学] S963.73[农业科学—水产养殖]