Two T vectors were generated by restriction endonuclease Xcm Ⅰ instead of Taq or other DNA polymerases to create the 3’T over hangs.A fragment of adenoviral genome position 10659-11865 was amplified by PCR and Xcm ...Two T vectors were generated by restriction endonuclease Xcm Ⅰ instead of Taq or other DNA polymerases to create the 3’T over hangs.A fragment of adenoviral genome position 10659-11865 was amplified by PCR and Xcm Ⅰ recognition sites were introduced to both ends of the PCR product.This fragment was cloned into the Sma Ⅰ site of pUC18 or the linearized pUC18 with its polylinker deleted.The recombinant plamids were cleaved with Xcm Ⅰ.the larger fragments generated which had 3’T over hangs at both ends were used as T vctors.Genes of rotavirus VP7 and the plasminogen k5 were successfully cloned into these two T vectors with recombination efficiency (recombinants/transformants×100%) of 100%,no blue/white clolny screening assay was needed.展开更多
应用原子力显微镜(atomic force microscope)对在云母表面铺展干燥的限制性内切酶(EcoR I)作用前后的pUC18质粒DNA分子进行扫描。扫描结果显示,质量浓度为1μg/mLpUC18质粒DNA分子在呈现典型的闭环环状结构,局部可见颗粒状或粗线型聚合...应用原子力显微镜(atomic force microscope)对在云母表面铺展干燥的限制性内切酶(EcoR I)作用前后的pUC18质粒DNA分子进行扫描。扫描结果显示,质量浓度为1μg/mLpUC18质粒DNA分子在呈现典型的闭环环状结构,局部可见颗粒状或粗线型聚合DNA片断。内切酶作用后,呈现网络状分布的细线状DNA分子。通过原子力显微镜对酶作用前后的质粒DNA分子的结构表征,对阐述酶切过程中DNA分子的结构变化机制打下基础。展开更多
Plasmid DNA was irradiated or implanted by mixed particle field(CR) or lithium-ion-beam to detect strand breaks.The primary results showed that mixed particle field could induce single and double strand breaks with po...Plasmid DNA was irradiated or implanted by mixed particle field(CR) or lithium-ion-beam to detect strand breaks.The primary results showed that mixed particle field could induce single and double strand breaks with positive linear-dose-effects;most of sequence changes induced by CR were point mutant.Lithium-ion-beam could induce strand breaks also,but it was only at dose of 20Gy.展开更多
文摘Two T vectors were generated by restriction endonuclease Xcm Ⅰ instead of Taq or other DNA polymerases to create the 3’T over hangs.A fragment of adenoviral genome position 10659-11865 was amplified by PCR and Xcm Ⅰ recognition sites were introduced to both ends of the PCR product.This fragment was cloned into the Sma Ⅰ site of pUC18 or the linearized pUC18 with its polylinker deleted.The recombinant plamids were cleaved with Xcm Ⅰ.the larger fragments generated which had 3’T over hangs at both ends were used as T vctors.Genes of rotavirus VP7 and the plasminogen k5 were successfully cloned into these two T vectors with recombination efficiency (recombinants/transformants×100%) of 100%,no blue/white clolny screening assay was needed.
文摘应用原子力显微镜(atomic force microscope)对在云母表面铺展干燥的限制性内切酶(EcoR I)作用前后的pUC18质粒DNA分子进行扫描。扫描结果显示,质量浓度为1μg/mLpUC18质粒DNA分子在呈现典型的闭环环状结构,局部可见颗粒状或粗线型聚合DNA片断。内切酶作用后,呈现网络状分布的细线状DNA分子。通过原子力显微镜对酶作用前后的质粒DNA分子的结构表征,对阐述酶切过程中DNA分子的结构变化机制打下基础。
文摘Plasmid DNA was irradiated or implanted by mixed particle field(CR) or lithium-ion-beam to detect strand breaks.The primary results showed that mixed particle field could induce single and double strand breaks with positive linear-dose-effects;most of sequence changes induced by CR were point mutant.Lithium-ion-beam could induce strand breaks also,but it was only at dose of 20Gy.