连接产物的脱盐浓缩有助于提高转化效率。而最佳的连接效率往往需要进行载体与外源片段不同摩尔比的预连接实验[9]。经过摸索发现,载体与外源片段在1∶5比例下,连接效率最高。 本实验所构建BAC文库克隆总数达3 456个,容量为链霉菌基因组DNA含量的17.3倍,平均插入片段达55kb,根据经验公式[10]计算,本文库得到任一基因的概率为99.99%,适合于单基因的克隆和分离。本文库的成功构建为进一步克隆链霉菌基因组重要功能基因提供了必备的物质平台。 参考文献 [1]Heia S.,Borgos S.E.F.,Sletta H.et al.Initiation of Polyene Macrolide Biosynthesis:Interplay between Polyketide Synthase Domains and Modules as Revealed via Domain Swapping,Mutagenesis,and Heterologous Complementation[J].Applied and Environmental Microbiology,2011,77(19):6982-6990. [2]刘志恒,姜成林.放线菌现代生物学与生物技术[M].北京:科学出版社,2004. [3]Wattanachaisaereekul S.,Lantz A.E.,Nielsen ML.,et al. Optimization of heterologous production of the polyketide 6-MSAS in Saccharomyces cerevisiae[J].Biotechnology and Bioengineering,2006,97(4):893-900. [4]Gagunashvili A.N.,Davidsson S.P.,Jonsson Z.O.,et al.Cloning and heterologus transcription of a polyketide synthase gene from the lichen Solorina crocea[J]. Mycological Research,2009:354-363. [5]Yuzawa S.,Kim W.,Katz L.,et al.Heterologous production of polyketides by modular type I polyketide synthases in Escherichia coli.,2011,23:1-9. [6]Shi X.,Zeng H.Y.,Xue Y.D.,et al. A pair of new BAC and BIBAC vectors that facilitate BAC/BIBAC library construction and intact large genomic DNA insert exchange[J].Plant Methods,2011,7:33. [7]王万群.武夷菌素产生菌CK-15细菌人工染色体(BAC)[D].北京:中国农业科学院,2008. [8]Wu C.C.,Nimm akayala P.,Santos F.A.,et al. Construction and characterization of a soybean bacterial artificial chromosome library and use of multiple complementary libraries for genome physical mapping [J]. Theor Appl Genet,2004,109(5):1041-1050. [9]邱芳,金德敏.温敏核不育水稻5460S细菌人工染色体文库的构建和鉴定[J].中国科学:C辑,1999,29(5):518-524. [10]Peterson D.G.,Tomkins J.P.,Frisch D.A.,et al. Construction of plant bacterial artificial chromosome(BAC)libraries An illustrated guide [J]. Journal of Agricultural Genomics,2000,5:1-100. |