The rate-limiting enzyme in the mev

The rate-limiting enzyme in the mevalonic acid （MVA）pathway which can lead to triterpenoid saponin glycyrhizic acid（GA）is 3-methylglutaryl-CoA reductase（HMGR）. In order to reveal the effect of copy number variation in the HMGR gene on the MVA pathway,the HMGR gene from Glycyrrhiza uralensis Fisch.（GuHMGR） was cloned and over-ecpressed in Pichia pastoris GS115. Six recombinant P. pastoris strains containing different copy number of the GuHMGR gene were obtained and the content of ergosterol was analyzed by HPLC. The results showed that all the recombinant P. pastoris strains contained more ergosterol than the negative control and the strains with 8 and 44 copy contained significantly more ergosterol than the other strains. However, as the copy number increased, the content of ergosterol showed an increasing-decreasing-increasing pattern. This study provides a rationale for increasing the content of GA through over-expressing the GuHMGR gene in cultivars of G. uralensis.

結果 (中文) 1:

速率限制酶在 mevalonic 酸 (MVA) 通路，从而导致三萜皂苷 glycyrhizic 酸 (GA) 是 3-戊二-CoA reductase(HMGR)。为了揭示在 HMGR 基因拷贝数变异 MVA 途径、 甘草 Fisch.(GuHMGR) 被克隆 HMGR 基因在毕赤酵母 GS115 以上 ecpressed 上的影响。获得六个包含不同拷贝数的 GuHMGR 基因的重组毕菌株和麦角固醇含量的高效液相色谱法进行了分析。结果表明，所有重组毕株包含更多的麦角固醇比阴性对照株 8 和 44 份载有比其他菌株显著更多麦角甾醇。然而，作为副本数量的增加，表明增加-减少-增加模式的麦角固醇含量。这项研究为提高 GA 含量通过过量表达 GuHMGR 基因品种甘草提供理论基础。

結果 (中文) 3:

限速酶的甲羟戊酸（MVA）途径导致三萜皂苷glycyrhizic酸（GA）是3-methylglutaryl-coa还原酶（HMGR）。为了揭示在MVA途径HMGR基因拷贝数变异的影响，从甘草HMGR基因。（guhmgr）克隆及在毕赤酵母占。六重组P得到的酵母菌株含有不同的guhmgr基因拷贝数和麦角甾醇含量的高效液相色谱法测定。结果表明，重组毕赤酵母菌株含有比阴性对照，用8和44拷贝菌株含有比其他菌株更明显更麦角甾醇麦角甾醇。但是，随着拷贝数的增加，麦角甾醇的含量呈上升-下降-上升的格局。本研究对于提高GA的含量，通过过表达在甘草品种guhmgr基因提供了理论基础。