五个链霉菌线型质粒端粒的克隆和分析  

Cloning and analysis of the telomeres of five Streptomyces linear plasmids

作　　者：杨勇[1] 代玉梅[1] 陈振华[1] 覃重军[1] 

机构地区：[1]中国科学院上海生命科学研究院植物生理生态研究所合成生物学重点实验室,上海200032

出　　处：《微生物学报》2010年第8期1008-1013,共6页Acta Microbiologica Sinica

基　　金：国家自然科学基金(30870067;30770045;30325003);国家"863计划"(2007AA021503);中国科学院知识创新工程项目(KSCX2-YW-G-014)~~

摘　　要：本室从西藏采集的土壤样品中分离到了一批链霉菌,利用脉冲电泳确定了其中5株链霉菌含有较小的线型质粒。【目的】克隆、测序和分析5个线型质粒的端粒。【方法】采用改良的"在凝胶中进行DNA碱处理和限制性内切酶酶切"的方法来克隆线型质粒的端粒DNA。【结果】克隆和测序了5个线型质粒的端粒DNA。通过与链霉菌典型端粒进行比较,发现这5个新的线型质粒的端粒序列同样含有多个回文序列。但是有的端粒保守的回文序列I不一定能够"折返"与内部序列配对形成"超级发卡"结构,回文序列的"突出环"不一定都为3nt。【结论】采用改良的方法克隆和鉴定了5个线型质粒新的端粒序列,这些新端粒的特征暗示:回文序列I的"折返"和3nt的回文序列的"突出环"不是端粒复制必需的。[Objective] Streptomyces strains were isolated from soil samples of Tibet,five small linear plasmids were detected by pulsed-field gel electrophoresis.[Objective ] Cloning,sequencing and analysis of telomeres of these plasmids.[Methods]The telomeres were cloned by a modified procedure— ＂alkaline treatment and enzyme digestion in gels＂.[Results]Telomeres of five linear plasmids were cloned and sequenced.Compared with the typical Streptomyces telomeres,the newly identified telomeres contained multiple palindromes,but some could not＂fold-back＂of their first conserved palindrome I with the internal palindromes to form a＂super-hairpin＂,and palindromes of some telomeres did not contain the 3-nt＂loop＂.[Conclusion]New telomere sequences were cloned by a modified procedure.Both foldingback of the telomere palindromes and 3-nt loop of palindromes varied among telomeres.

关 键 词：链霉菌 线型质粒 端粒 复制 

分 类 号：Q933[生物学—微生物学]