ARTP-DES复合诱变结合前体耐受性选育达托霉素高产菌株

Breeding of high daptomycin-producing strain by ARTP-DES compound mutagenesis combined with precursor tolerance

摘要:

为提高玫瑰孢链霉菌（Streptomyces roseosporus）AN-126的达托霉素（Daptomycin）产量，对菌株AN-126进行ARTP-DES复合诱变，并结合癸酸钠耐受性筛选，最终获得一株达托霉素高产菌株RR-447，摇瓶产量为101.41 mg/L，是出发菌株的2.44倍。传代实验表明，该菌株高产性能稳定遗传。对突变前后菌株的形态特征以及基因指纹图谱进行分析，结果显示突变菌株与出发菌株在形态学特征有明显差异，且高产菌株RR-447 基因组DNA在1.5 kb~2.0 kb之间存在一条特异性条带。通过在5L发酵罐中流加前体物质癸酸钠，菌株RR-447达托霉素产量达到521.39 mg/L。研究结果表明，ARTP-DES复合诱变结合癸酸钠耐受性是选育达托霉素高产菌株的一种有效育种手段，为达托霉素工业微生物育种以及其他菌株改良提供了技术参考。

Abstract:

Inorder to increase the daptomycin yield of Streptomyces roseosporus AN-126, the strain AN-126 was mutated by ARTP-DES compound mutagenesis combined with sodium decanoate tolerance. A mutant strain RR-447 with a yield of 101.41 mg/L was obtained, which was 2.44 times that of the strain AN-126. The genetic stability experiment showed that the high yield performance of the strain RR-447 was stably inherited. The morphological characteristics and gene fingerprints of strains AN-126 and RR-447 were analyzed. The strain RR-447 was not only different from strain AN-126 in morphological characteristics, but also had a specific band between 1.5 kb and 2.0 kb in its genome DNA. In 5 L fermentation tank, the daptomycin yield of strain RR-447 reached a maximum of 521.39 mg/L by adding sodium decanoate. The results show that ARTP-DES compound mutagenesis combined with sodium decanoate tolerance is an effective breeding method for breeding high-yield daptomycin strains, which provides a technical reference for industrial microbial breeding of daptomycin and other strains improvement.