酿酒酵母人工杂合启动子与天然启动子活性比较

Activity Comparison of the Artificial Hybrid Promoter with Its Native Promoter in Saccharomyces cerevisiae

系统地比较了人工启动子P_(aTEF1)与天然启动子PTEF1和PTDH3在不同条件下的活性差别,结果表明,人工启动子P_(aTEF1)的活性并不是在任何条件下都高于天然启动子的活性,而与宿主、培养基以及细胞生长阶段有关。在3个宿主背景中,BY4741中P_(aTEF1)的活性最高,而LX03中最低。在YPD100中,人工启动子P_(aTEF1)活性分别为天然启动子PTEF1和PTDH3活性的1.4-4.6倍和0.9-2.0倍;而在YPE(5%和7%)中,P_(aTEF1)活性与PTEF1和PTDH3活性之比在0.7-1.3以及0.8-1.3之间。在YPE中培养时,P_(aTEF1)的活性为在YPD100中培养时的1.7-2.0倍,PTEF1和PTDH3的活性在YPE中为YPD100中培养时的2.7-7.1倍和1.3-3.4倍,启动子在YPE中的活性较YPD100中更高,但人工启动子的活性变化较天然启动子更小。此外,在不同遗传背景的菌株中,启动子活性从对数期早期到对数期中期和从对数期中期到稳定期的变化趋势不同。

The responses of promoter strengths of artificial TEF1 promoter（P（aTEF1））and native promoter PTEF1 as well as PTDH3 werecomprehensively compared. The strength of P（aTEF1） was not always higher than PTEF1,but varied along with the genetic background of host,medium,and cell growth phase. Among the three investigated hosts,P（aTEF1） showed the highest strength in BY4741,while the lowest in LX03.The strengths of P（aTEF1） were 1.4-4.6 and 0.9-2.0 times of those of native promoters（PTEF1 and PTDH3）in YPD100 medium,respectively. Theactivities of P（aTEF1） in YPE（5% and 7%）were 0.7-1.3 and 0.8-1.3 times of PTEF1 and PTDH3. The activity of P（aTEF1） in YPE was 1.7-2.0 times ofthat in YPD100,whereas 2.7-7.1 and 1.3-3.4 times for PTEF1 and PTDH3,respectively. The activities of the promoters in YEP were higher thanthose in YPD100,however,the activity variation of artificial promoters was less than that of native promoter. In addition,the variation trends ofpromoter strengths from early-log to mid-log phase and from mid-log to stationary phase varied in different host strains.