Asymmetry and Extent of In Vivo Transcripition of R-Plasmid Deoxyribonucleic Acid in Escherichia coli
Asymmetry and Extent of In Vivo Transcripition of R-Plasmid Deoxyribonucleic Acid in Escherichia coli
复制标题
大肠杆菌中 R 质粒脱氧核糖核酸体内转录的不对称性和程度
DOI：
10.1128/jb.120.3.1274-1278.1974
复制
发表时间：
1974
影响因子：
3.2
通讯作者：
E. Spingler
中科院分区：
文献类型：
--
作者：
D. Vapnek;E. Spingler
用R-质粒DNA(R538-1drd)和体内合成的RNA进行了脱氧核糖核酸-核糖核酸(DNA-RNA)杂交研究。从大肠杆菌K-12中提取R-质粒DNA，并用氯化铯-多聚尿酸-多鸟苷梯度分离互补链。将分离的DNA链与纯化的R-质粒细胞RNA进行DNA-RNA杂交。结果表明，R-质粒DNA在体内发生了不对称转录。仅与H链(氯化铯-多尿酸-聚鸟氨酸中密度较高的链)杂交。通过测定RNA-DNA杂交在CSCL梯度中的密度，估计R-质粒DNA中超过60%的核苷酸序列是在对数生长的大肠杆菌细胞中转录的。在没有携带R-质粒的大肠杆菌细胞中未检测到R-质粒特异性RNA。
Deoxyribonucleic acid-ribonucleic acid (DNA-RNA) hybridization studies have been performed with R-plasmid DNA (R538-1drd) and in vivo-synthesized RNA. R-plasmid DNA was isolated from Escherichia coli K-12, and the complementary strands were separated in cesium chloride-polyuridylic acid-polyguanylic acid gradients. DNA-RNA hybridization was performed with the separated DNA strands and RNA purified from R-plasmid-carrying cells. The results demonstrated that an asymmetric transcription of the R-plasmid DNA occurs in vivo. Hybridization was only detected with the H strand (denser strand in cesium chloride-polyuridylic acid-polyguanylic acid). By determining the density of the RNA-DNA hybrid in CsCl gradients, it was estimated that greater than 60% of the nucleotide sequences in the R-plasmid DNA are transcribed in logarithmically growing E. coli cells. No R-plasmid-specific RNA was detected in E. coli cells that did not carry the plasmid.