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
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
Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and qua...Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and quality.A different mutant strain with lower acetaldehyde production and improved ethanol tolerance was constructed using the ARTP-ALE mutagenesis strategy with 4-methylpyrazole-disulfiram.As a result of the mutation,the alcohol dehydrogenase activity of the mutant strain decreased to about 71.22%of that of the wild-type strain.At the same time,the fermentation properties and genetic stability of the newly screened strain showed slight differences from the wild-type strain,and there were no safety concerns regarding industrial use of the mutant strain.展开更多
为达到同步糖化发酵(simultaneous saccharification and fermentation,SSF)中菌株高温耐受能力提升的目的,该文以实验室保藏的马克斯克鲁维酵母(Kluyveromyces marxianus)GX-UN120为出发菌株,采用常压室温等离子体(atmospheric and roo...为达到同步糖化发酵(simultaneous saccharification and fermentation,SSF)中菌株高温耐受能力提升的目的,该文以实验室保藏的马克斯克鲁维酵母(Kluyveromyces marxianus)GX-UN120为出发菌株,采用常压室温等离子体(atmospheric and room temperature plasma,ARTP)诱变技术,结合高温胁迫筛选获得1株具有较好耐高温能力和产乙醇能力的菌株GX-UN127。结果表明,诱变菌株GX-UN127在48℃培养72 h,OD_(600)可达到1.27(原始菌株无法生长)。同时,当以100 g/L麸皮为原料,45℃SSF 12 h,诱变菌株GX-UN127发酵乙醇的产量可达7.6 g/L,较出发菌株提升15.2%。在此基础上,结合生理指标和代谢组学进一步探究诱变菌株耐受高温的生理机制,研究表明半胱氨酸和蛋氨酸代谢、谷胱甘肽代谢、精氨酸和脯氨酸代谢、甘油磷脂代谢等代谢途径与诱变菌株GX-UN127的更强高温耐受性密切相关。此诱变选育耐高温马克斯克鲁维酵母菌株的方案可行,为该类菌株进行SSF生产燃料乙醇提供理论支持。展开更多
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。
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.
基金Supported by Heilongjiang Natural Science Foundation Joint Guide Project(LH2019C022)。
文摘Higher levels of acetaldehyde in beer are one of the major concerns in the current beer industry.Yeast produces acetaldehyde during alcoholic fermentation,and its modification significantly affects beer flavor and quality.A different mutant strain with lower acetaldehyde production and improved ethanol tolerance was constructed using the ARTP-ALE mutagenesis strategy with 4-methylpyrazole-disulfiram.As a result of the mutation,the alcohol dehydrogenase activity of the mutant strain decreased to about 71.22%of that of the wild-type strain.At the same time,the fermentation properties and genetic stability of the newly screened strain showed slight differences from the wild-type strain,and there were no safety concerns regarding industrial use of the mutant strain.
文摘为达到同步糖化发酵(simultaneous saccharification and fermentation,SSF)中菌株高温耐受能力提升的目的,该文以实验室保藏的马克斯克鲁维酵母(Kluyveromyces marxianus)GX-UN120为出发菌株,采用常压室温等离子体(atmospheric and room temperature plasma,ARTP)诱变技术,结合高温胁迫筛选获得1株具有较好耐高温能力和产乙醇能力的菌株GX-UN127。结果表明,诱变菌株GX-UN127在48℃培养72 h,OD_(600)可达到1.27(原始菌株无法生长)。同时,当以100 g/L麸皮为原料,45℃SSF 12 h,诱变菌株GX-UN127发酵乙醇的产量可达7.6 g/L,较出发菌株提升15.2%。在此基础上,结合生理指标和代谢组学进一步探究诱变菌株耐受高温的生理机制,研究表明半胱氨酸和蛋氨酸代谢、谷胱甘肽代谢、精氨酸和脯氨酸代谢、甘油磷脂代谢等代谢途径与诱变菌株GX-UN127的更强高温耐受性密切相关。此诱变选育耐高温马克斯克鲁维酵母菌株的方案可行,为该类菌株进行SSF生产燃料乙醇提供理论支持。