Swinton D, Hattman S, Crain P F, Cheng C S, Smith D L, McCloskey J A
Proc Natl Acad Sci U S A. 1983 Dec;80(24):7400-4. doi: 10.1073/pnas.80.24.7400.
Bacteriophage Mu encodes a protein that modifies approximately equal to 15% of DNA adenine residues to a new and unusual form. Modified DNA was enzymatically digested to deoxynucleosides, and the products were fractionated by HPLC. A modified adenine nucleoside, designated dA'x, was purified and its molecular structure was established by mass spectrometry. We show that dA'x is alpha-N-(9-beta-D-2'-deoxyribofuranosylpurin-6-yl)-glycinamide. The dA'x obtained from DNA was indistinguishable from the synthetic product with respect to its chromatographic behavior (HPLC and gas chromatography) and mass spectrum. Acid hydrolysis degrades dA'x to produce N6-carboxymethyladenine; this compound corresponds to the base Ax observed in earlier studies.
噬菌体Mu编码一种蛋白质,该蛋白质可将约15%的DNA腺嘌呤残基修饰成一种新的异常形式。将修饰后的DNA酶解为脱氧核苷,产物通过高效液相色谱法(HPLC)进行分离。一种名为dA'x的修饰腺嘌呤核苷被纯化出来,其分子结构通过质谱法确定。我们发现dA'x是α-N-(9-β-D-2'-脱氧呋喃核糖基嘌呤-6-基)-甘氨酰胺。从DNA中获得的dA'x在色谱行为(HPLC和气相色谱)和质谱方面与合成产物没有区别。酸水解会使dA'x降解产生N6-羧甲基腺嘌呤;该化合物与早期研究中观察到的碱基Ax相对应。