巨大芽孢杆菌KM核酸的甲基化碱基：与大肠杆菌的比较。
Methylated bases of Bacillus megaterium KM nucleic acids: comparison with Escherichia coli.
作者信息
Wachsman J T, Irwin V
出版信息
J Bacteriol. 1970 Nov;104(2):814-8. doi: 10.1128/jb.104.2.814-818.1970.
Parallel studies were performed with methionineless derivatives of Escherichia coli 15 T(-) and Bacillus megaterium KM: T(-). Methylated bases are present in the total cell ribonucleic acid (RNA) of B. megaterium. The level of RNA methylation in E. coli is about 60% greater than that in B. megaterium. Although E. coli deoxyribonucleic acid (DNA) was found to contain 0.12% 5-methylcytosine (5-MC) and 0.24% 6-methylaminopurine (6-MA), methylated bases were not detected in the DNA of B. megaterium. Assuming a molecular weight of 7 x 10(9) daltons for B. megaterium DNA, it was calculated that this organism could not contain more than one molecule of 5-MC or 6-MA per genome, and that possibly no methylated bases were present. Methylated bases were also not detected in the DNA of thymine-starved B. megaterium. Crude extracts of this organism possess RNA methylase activity but no detectable DNA methylase activity.
对大肠杆菌15 T(-)和巨大芽孢杆菌KM: T(-)的无甲硫氨酸衍生物进行了平行研究。甲基化碱基存在于巨大芽孢杆菌的总细胞核糖核酸（RNA）中。大肠杆菌中RNA甲基化水平比巨大芽孢杆菌中的高约60%。虽然发现大肠杆菌脱氧核糖核酸（DNA）含有0.12%的5-甲基胞嘧啶（5-MC）和0.24%的6-甲基腺嘌呤（6-MA），但在巨大芽孢杆菌的DNA中未检测到甲基化碱基。假设巨大芽孢杆菌DNA的分子量为7×10(9)道尔顿，经计算该生物体每个基因组中含有的5-MC或6-MA分子不超过一个，甚至可能不存在甲基化碱基。在胸腺嘧啶饥饿的巨大芽孢杆菌的DNA中也未检测到甲基化碱基。该生物体的粗提取物具有RNA甲基酶活性，但未检测到DNA甲基酶活性。
Zotero 插件