非随机方法构建酿酒酵母基因工程菌

酿酒酵母是基因工程产品研究和生产的一个重要表达系统，表达载体和宿主细胞是构成表达系统的两大要素，虽然外源基因表达的方式、强度主要由表达载体控制．但宿主细胞的选择对最终获取产品的质量和数量也具有十分关键的作用。酿酒酵母基因工程宿主菌除要求具有高的DNA转化效率、细胞生长密度和稳定性、低的内源蛋白水解酶活性外，还必须具备与表达载体相对应的营养缺陷筛选标记，用传统随机诱变方法得到的营养缺陷变异株，因含有本底和隐性突变，在细胞生长密度和稳定性方面往往不能满足基因工程产品研究和生产的要求，甚至不能有效地表达外源基因。本文报道用重组技术，通过非随机方法构建了酿酒酵母基因工程宿主茁。研究表明用该方法得到的宿主菌在细胞生长密度、稳定性和表达外源基因方面优于用传统随机诱变方法得到的宿主菌。

Construction of Engineering Host by Non random Method in Sacchromyces cerevisiae

A yeast engineering host,GJ30,was construction by nonrandom method.GJ30 derivated from wild type yeast have leu 2 - and ura 3 - deficients which can be used as selecting markers.The PCR analysis showed that the homologous recombinations were happened in the leu2 and ura3 locus of GJ30 respectively.The biological properties (cell growth density,stability and efficiency for gene expression) of GJ30 were compared with other several yeast tains.The results showed that GJ30 is a suitable host strain for expression of foreign genes.