[关键词]
[摘要]
本文采用新型常压室温等离子体(ARTP)生物诱变育种技术,基于48孔板高通量筛选获得一株L-苏氨酸产量明显提高的突变株(1905#)。相比较与出发菌株,在相同的发酵培养条件下,1905#突变株鲁棒性较好、生长速率加快,最佳温度(37℃)和pH(7.2)基本一致,能耐受更低的pH值。孔板初筛结果表明苏氨酸浓度提高了133.59%,并且对摇瓶发酵过程进行了研究,相比较与出发菌株糖代谢速率加快,产酸强度提高,苏氨酸浓度提高了99.6%。经50次传代,1905#突变株表现出很好的遗传稳定性,为产业化水平的提高提供了坚实的理论基础和数据参考。
[Key word]
[Abstract]
To obtain mutants with high threonine productivity, atmospheric and room temperature plasmas (ARTP) mutation technique was used and combined with high throughput screening based on 48 well plates. Mutant 1905# was screened with high threoine productivity. Compared with original strain under the same fermentation conditions, the mutant 1905# showed better robustness and faster growth rate. The mutant showed similar optimum temperature (37 ℃) and pH (7.2) to the original strain, but it can tolerate lower pH. In the preliminary plate screening, the threonine concentration increased by 133.59%. For the flask fermentation process, the mutant 1905# showed higher glucose consumption and enhanced threonine productivity The threonine concentration by the mutant was increased by 99.6% compared with that by the original. The 1905# mutant showed high genetic stability after 50 subcultures, offering theoretical reference for further increasing threonine industrialization level
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[基金项目]
清华大学自主科研计划项目(2011Z01019)