Steroid medication is used extensively in clinical applications and comprises a large and vital part of the pharmaceutical industry. However, the difficulty of separating 4-androstene-3,17-dione （AD） from 1,4-andros...Steroid medication is used extensively in clinical applications and comprises a large and vital part of the pharmaceutical industry. However, the difficulty of separating 4-androstene-3,17-dione （AD） from 1,4-androstadiene- 3,17-dione （ADD） restricts the application of the microbial transformation of phytosterols in the industry. A novel at- mospheric and room temperature plasma （ARTP） treatment, which employs helium as the working gas, was used to generate Mycobacterium neoaurum mutants producing large amounts of AD. After treatment of cultures with ARTP, four mutants were selected using a novel screening method with a color assay. Among the mutants, M. neoaurum ZADF-4 was considered the best candidate for industrial application. When the fermentation medium contained 15 g/L phytosterols and was cultivated on a rotary shaker at 160 r/min at 30 ~C for 7 d, （6.28＋0.11） g/L of AD and （0.82＋0.05） g/L of ADD were produced by the ZADF-4 mutant, compared with （4.83＋0.13） g/L of AD and （2.34＋0.06） g/L of ADD by the original strain, Iv~. neoaururn ZAD. Compared with ZAD, the molar yield of AD increased from 48.3% to 60.3% in the ZADF-4 mutant. This result indicates that ZADF-4 may have potential for industrial production of AD.展开更多
对异养小球藻进行常压室温等离子体(Atmospheric and Room Temperature Plasma,ARTP)诱变确定最佳诱变条件,在最佳诱变条件下筛选突变株,并开展突变株的摇瓶培养再验证试验、遗传稳定性试验、50 L发酵罐试验。结果表明,异养小球藻的最...对异养小球藻进行常压室温等离子体(Atmospheric and Room Temperature Plasma,ARTP)诱变确定最佳诱变条件,在最佳诱变条件下筛选突变株,并开展突变株的摇瓶培养再验证试验、遗传稳定性试验、50 L发酵罐试验。结果表明,异养小球藻的最佳致死时间为50 s;得到6株突变株,且其细胞数多于出发菌株、质量浓度明显高于出发菌株;突变性能可以稳定遗传,突变株可提前24 h到达发酵终点,发酵液中油脂产量高于出发菌株。展开更多
利用常温常压等离子体诱变(Atmospheric and Room Temperature Plasma, ARTP)蜡状芽孢杆菌,筛选获得酶活提升的菌株。结果表明,蜡状芽孢杆菌在种子液中培养6 h可达到对数期中后期,常温常压等离子体诱变时间为60 s时,蜡状芽孢杆菌的致死...利用常温常压等离子体诱变(Atmospheric and Room Temperature Plasma, ARTP)蜡状芽孢杆菌,筛选获得酶活提升的菌株。结果表明,蜡状芽孢杆菌在种子液中培养6 h可达到对数期中后期,常温常压等离子体诱变时间为60 s时,蜡状芽孢杆菌的致死率达到85%,筛选得到一株壳聚糖酶活性提高13.19%的突变株,然后进行酶活稳定性验证,经六代培养的平均酶活为9.643367 U/mL,波动在5%之内,表明其产酶量高,稳定性强,可用于后续出发菌株。诱变后菌株经电镜观察,发现菌落形态无明显变化,但是菌株的个体形态发生了变化,比原始菌株细长,证明酶活提高是ARTP诱变起到的作用。展开更多
基金supported by the National Basic Research Program(973)of China(No.2012CB725202)the National High-Tech R&D Program(863)of China(No.2011AA02A211)+4 种基金the National Natural Science Foundation of China(No.21276110)the Fundamental Research Funds for the Central Universities(Nos.JUSRP51306A and JUSRP11545)the National 111 Project of China’s Higher Education(No.111-2-06)the Program of the Key Laboratory of Industrial Biotechnology,Ministry of Education,China(No.KLIB-KF201406)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘Steroid medication is used extensively in clinical applications and comprises a large and vital part of the pharmaceutical industry. However, the difficulty of separating 4-androstene-3,17-dione （AD） from 1,4-androstadiene- 3,17-dione （ADD） restricts the application of the microbial transformation of phytosterols in the industry. A novel at- mospheric and room temperature plasma （ARTP） treatment, which employs helium as the working gas, was used to generate Mycobacterium neoaurum mutants producing large amounts of AD. After treatment of cultures with ARTP, four mutants were selected using a novel screening method with a color assay. Among the mutants, M. neoaurum ZADF-4 was considered the best candidate for industrial application. When the fermentation medium contained 15 g/L phytosterols and was cultivated on a rotary shaker at 160 r/min at 30 ~C for 7 d, （6.28＋0.11） g/L of AD and （0.82＋0.05） g/L of ADD were produced by the ZADF-4 mutant, compared with （4.83＋0.13） g/L of AD and （2.34＋0.06） g/L of ADD by the original strain, Iv~. neoaururn ZAD. Compared with ZAD, the molar yield of AD increased from 48.3% to 60.3% in the ZADF-4 mutant. This result indicates that ZADF-4 may have potential for industrial production of AD.
文摘对异养小球藻进行常压室温等离子体(Atmospheric and Room Temperature Plasma,ARTP)诱变确定最佳诱变条件,在最佳诱变条件下筛选突变株,并开展突变株的摇瓶培养再验证试验、遗传稳定性试验、50 L发酵罐试验。结果表明,异养小球藻的最佳致死时间为50 s;得到6株突变株,且其细胞数多于出发菌株、质量浓度明显高于出发菌株;突变性能可以稳定遗传,突变株可提前24 h到达发酵终点,发酵液中油脂产量高于出发菌株。
文摘利用常温常压等离子体诱变(Atmospheric and Room Temperature Plasma, ARTP)蜡状芽孢杆菌,筛选获得酶活提升的菌株。结果表明,蜡状芽孢杆菌在种子液中培养6 h可达到对数期中后期,常温常压等离子体诱变时间为60 s时,蜡状芽孢杆菌的致死率达到85%,筛选得到一株壳聚糖酶活性提高13.19%的突变株,然后进行酶活稳定性验证,经六代培养的平均酶活为9.643367 U/mL,波动在5%之内,表明其产酶量高,稳定性强,可用于后续出发菌株。诱变后菌株经电镜观察,发现菌落形态无明显变化,但是菌株的个体形态发生了变化,比原始菌株细长,证明酶活提高是ARTP诱变起到的作用。
