利用基因组改组技术选育阿维拉霉素高产菌

Screening and Breeding Strains Producing High-yield Avilamycin by Genome Shuffling

为选育阿维拉霉素高产菌株,对野生型绿色产色链霉菌(Streptomyces viridochromogenes)Tü57进行传统物理和化学诱变,并获得一系列以阿维拉霉素A的含量为指标的正向突变体,再采用基因组改组技术将不同的正向突变体进行融合杂交,获得融合子。在筛选融合子的过程中,采用传统薄层色谱(TLC)和管碟法(二剂量法)结合进行初筛、高效液相色谱法进行复筛的筛选策略。经过基因组改组,筛选得到一株高产菌株R708,其在摇瓶实验中阿维拉霉素A产量达到0.208 g/L,比野生菌株提高了20倍。基因组改组选育阿维拉霉素高产菌,能提高子代菌株的遗传多样性,比传统诱变选育更快速有效。

In order to screen strain producing high-yield avilamycin by mutagenesis, a wild-type strain Streptomyces viridochromogenes Tu57 was treated by a series of traditionally physical and chemical mutagenesis, resulting in the acquisition of numbers of forward mutants while judged by the great improvement in avilamycin A production. Genome shuffling was then carried out to fuse different sources of forward mutants, following with various fusants harvestry. The screening strategy adopted the combination method of thin layer chromatography （TLC） and cylinder-plate （two dosages technique） as the primary test, and high performance liquid chromatography （HPLC） as the secondary test. A mutant producing high-yield avilamycin, designated as R708, was obtained. The yield of avilamycin A from this mutant reached to 0.208 g/L in the shake flask experiment, which was a 20-fold increment compared to that of the wild-type strain. Our conclusion is that genome shuffling could increase the genetic diversity of the offspring strains; therefore this method is more quickly and efficiently than traditional mutagenesis in breeding strains producing high-yield avilamycin.