【目的】比较两种酵母培养物及其代谢成分的差异,为指导酵母培养物的生产及应用提供参考。【方法】材料为1种自研酵母培养物与达农威益康XP酵母培养物,利用非靶标代谢组学UHPLC-QTOF-MS技术,分析比较二者代谢产物成分及差异。【结果】(1...【目的】比较两种酵母培养物及其代谢成分的差异,为指导酵母培养物的生产及应用提供参考。【方法】材料为1种自研酵母培养物与达农威益康XP酵母培养物,利用非靶标代谢组学UHPLC-QTOF-MS技术,分析比较二者代谢产物成分及差异。【结果】(1)在二级类别注释下,正、负离子模式分别注释到614、497个化合物,主要代谢类别为有机酸,核苷、核苷酸及其衍生物,氨基酸及其衍生物,两种酵母培养物均无特有代谢成分,只在含量上有显著(P<0.05)差异。(2)共237个差异代谢物在正离子模式检出,176个显著(P<0.05)上调表达,61个显著(P<0.05)下调表达;136个差异代谢物在负离子模式检出,64个显著(P<0.05)上调表达,72个显著(P<0.05)下调表达。(3)差异代谢物的KEGG(Kyoto Encyclopedia of Genes and Genomes)富集分析主要集中在丙氨酸、天冬氨酸和谷氨酸等代谢通路。【结论】自研酵母培养物与达农威益康XP的代谢产物含量存在显著差异,但其发酵原料及工艺更简便,并含有多种具药理、生理作用的代谢成分,有潜在应用价值。展开更多
Curing of Bacillus subtilis plasmid using sodium dodecyl sulfate (SDS)was studied in order to obtain a host strain. An overnight culture of Bacillus subtilis 24/pMX45 was used to inoculate fresh LB containing SDS (0-0...Curing of Bacillus subtilis plasmid using sodium dodecyl sulfate (SDS)was studied in order to obtain a host strain. An overnight culture of Bacillus subtilis 24/pMX45 was used to inoculate fresh LB containing SDS (0-0.008%). No growth of 24/pMX45 was observed when LB contained an SDS concentration of 0.006% or greater, and the sublethal concentration (w/v) of SDS was 0.005% with a killing rate of 99%. Samples were diluted and plated on LB agar, individual colonies were randomly picked to a selective agar medium by tooth to screen for loss of plasmid-encoded erythomycin resistance. CsCl-EtBr gradient centrifugation and plasmid DNA profile demonstrated that plasmid-cured derivative A7 has completely lost its plasmid. A7 had a shorter lag, and its cell concentration was consistently higher than that of the 24/pMX45. Elimination of the plasmid was first observed after 24/pMX45 had been treated with SDS for 8 h. The percent elimination then continued to increase until about 22 h, after which the fraction of cured cell in the population remained constant. Plasmid cured cell numbers were measured in a separate control culture of 24/pMX45 untreated by SDS. No spontaneous loss of pMX45 was observed after 24/pMX45 were incubated for 24 h and 48 h with shaking at 37 ℃.These results suggested that SDS can be used as curing agent to eliminate the plasmid of Bacillus subtilis.展开更多
A bacterium B2 isolated from the Tianshan glacier of Xinjiang could produce blue pigments.According to 16S rDNA analysis, this isolate belonged to Duganella Genus .Two compounds were separated and purified from the cu...A bacterium B2 isolated from the Tianshan glacier of Xinjiang could produce blue pigments.According to 16S rDNA analysis, this isolate belonged to Duganella Genus .Two compounds were separated and purified from the cultivated Duganella B2 , named Blue-Ⅰand Blue-Ⅱ, respectively.From the spectra data of UV, MS and NMR of the compounds, Blue-Ⅰwas confirmed to be deoxyviolacein and Blue-Ⅱ was violacein.Blue-Ⅰand Blue-Ⅱ had the respective molecular weights of 327.2 and 343.2,and showed the characteristic absorption peaks at the respective 560 and 572 nm within the visible light range in ethanol solution.These results will be useful for developing the bioprocess for producing bacterial violacein.展开更多
文摘【目的】比较两种酵母培养物及其代谢成分的差异,为指导酵母培养物的生产及应用提供参考。【方法】材料为1种自研酵母培养物与达农威益康XP酵母培养物,利用非靶标代谢组学UHPLC-QTOF-MS技术,分析比较二者代谢产物成分及差异。【结果】(1)在二级类别注释下,正、负离子模式分别注释到614、497个化合物,主要代谢类别为有机酸,核苷、核苷酸及其衍生物,氨基酸及其衍生物,两种酵母培养物均无特有代谢成分,只在含量上有显著(P<0.05)差异。(2)共237个差异代谢物在正离子模式检出,176个显著(P<0.05)上调表达,61个显著(P<0.05)下调表达;136个差异代谢物在负离子模式检出,64个显著(P<0.05)上调表达,72个显著(P<0.05)下调表达。(3)差异代谢物的KEGG(Kyoto Encyclopedia of Genes and Genomes)富集分析主要集中在丙氨酸、天冬氨酸和谷氨酸等代谢通路。【结论】自研酵母培养物与达农威益康XP的代谢产物含量存在显著差异,但其发酵原料及工艺更简便,并含有多种具药理、生理作用的代谢成分,有潜在应用价值。
文摘Curing of Bacillus subtilis plasmid using sodium dodecyl sulfate (SDS)was studied in order to obtain a host strain. An overnight culture of Bacillus subtilis 24/pMX45 was used to inoculate fresh LB containing SDS (0-0.008%). No growth of 24/pMX45 was observed when LB contained an SDS concentration of 0.006% or greater, and the sublethal concentration (w/v) of SDS was 0.005% with a killing rate of 99%. Samples were diluted and plated on LB agar, individual colonies were randomly picked to a selective agar medium by tooth to screen for loss of plasmid-encoded erythomycin resistance. CsCl-EtBr gradient centrifugation and plasmid DNA profile demonstrated that plasmid-cured derivative A7 has completely lost its plasmid. A7 had a shorter lag, and its cell concentration was consistently higher than that of the 24/pMX45. Elimination of the plasmid was first observed after 24/pMX45 had been treated with SDS for 8 h. The percent elimination then continued to increase until about 22 h, after which the fraction of cured cell in the population remained constant. Plasmid cured cell numbers were measured in a separate control culture of 24/pMX45 untreated by SDS. No spontaneous loss of pMX45 was observed after 24/pMX45 were incubated for 24 h and 48 h with shaking at 37 ℃.These results suggested that SDS can be used as curing agent to eliminate the plasmid of Bacillus subtilis.
文摘A bacterium B2 isolated from the Tianshan glacier of Xinjiang could produce blue pigments.According to 16S rDNA analysis, this isolate belonged to Duganella Genus .Two compounds were separated and purified from the cultivated Duganella B2 , named Blue-Ⅰand Blue-Ⅱ, respectively.From the spectra data of UV, MS and NMR of the compounds, Blue-Ⅰwas confirmed to be deoxyviolacein and Blue-Ⅱ was violacein.Blue-Ⅰand Blue-Ⅱ had the respective molecular weights of 327.2 and 343.2,and showed the characteristic absorption peaks at the respective 560 and 572 nm within the visible light range in ethanol solution.These results will be useful for developing the bioprocess for producing bacterial violacein.
