Wang Shuyang, Bo Yongheng, Chen Jihong, Zhou Xiang, Li Wenjian, Liang Jianpin, Dong Miaoyin
Institute of Modern Physics Chinese Academy of Sciences Lanzhou Gansu P. R. China.
Institute of Veterinary Drug Quality Inspection of Shandong Province Jinan P. R. China.
Eng Life Sci. 2018 Sep 12;18(10):711-720. doi: 10.1002/elsc.201800094. eCollection 2018 Oct.
The biggest challenge in anabolism research is to improve the stability and safety of microbial metabolite production on an industrial scale. One class of metabolites, avermectins, are produced by . In this study, an avermectin B1a-high-producing mutant was produced using heavy ion mutagenesis and selected based on LTQ-MS and HPLC-UV method. The mutants ZJAV-Y-147 and ZJAV-Y-HS, obtained after subjecting the spores of to 70 Gy of C heavy ion irradiation, were found to best improve the avermectin B1a production (4822.23 μg/mL and 4632.17 μg/mL, respectively). These two mutants' yielded of avermectin B1a were 2-fold high than the original strains. The DNA of the original and mutant strains were analyzed by RAPD technique with four random primers after irradiated with ion beam irradiation. The results show that different high-titer strains contain different genetic modifications. In addition, the mutation position, mutation type and sequence context of all mutations of gene in two mutants were researched, and the production of avermectin B1a and its analogues of wild-type and mutants were analyzed by fermenting 240 h, which was suggested that the partial base deletion of aveI gene may be the key sites for increasing avermectin B1a production after the C-ion irradiation. All these modifications promote increased avermectin biosynthesis, leading to multiple high-titer strains. The results demonstrate that this is an effective approach to engineer as a host for the biological production of commercial analogs.
合成代谢研究中最大的挑战是在工业规模上提高微生物代谢产物生产的稳定性和安全性。一类代谢产物，阿维菌素，是由……产生的。在本研究中，利用重离子诱变产生了一株高产阿维菌素B1a的突变体，并基于LTQ-MS和HPLC-UV方法进行筛选。将……的孢子用70 Gy的碳重离子辐照后获得的突变体ZJAV-Y-147和ZJAV-Y-HS，被发现能最好地提高阿维菌素B1a的产量（分别为4822.23μg/mL和4632.17μg/mL）。这两个突变体的阿维菌素B1a产量比原始菌株高2倍。用离子束辐照后，用四种随机引物通过RAPD技术分析原始菌株和突变菌株的DNA。结果表明，不同的高产……菌株含有不同的基因修饰。此外，研究了两个突变体中……基因所有突变的突变位置、突变类型和序列背景，并通过240小时发酵分析了野生型和突变体的阿维菌素B1a及其类似物的产量，结果表明aveI基因的部分碱基缺失可能是碳离子辐照后提高阿维菌素B1a产量的关键位点。所有这些修饰都促进了阿维菌素生物合成的增加，从而产生了多个高产……菌株。结果表明，这是一种将……工程改造为商业类似物生物生产宿主的有效方法。
