Lessor R A, Gibson K J, Leonard N J
Biochemistry. 1984 Aug 14;23(17):3868-73. doi: 10.1021/bi00312a012.
2'-Deoxy-lin-benzoadenosine has been synthesized via reductive deoxygenation of 2-(beta-D-ribofuranosyl)-8-(methylthio)imidazo[4,5-g]quinazoline. The 5'-mono-, 5'-di-, and 5'-triphosphates have been prepared by chemical and/or enzymatic methods. The 5'-diphosphate was found to be a substrate for phosphorylation by pyruvate kinase and was compared with various natural and extended substrates in kinetic assays. When 2'-deoxy-lin-benzoadenosine 5'-triphosphate was tested in a nick-translation experiment with Escherichia coli DNA polymerase I, a very low level of 32P incorporation from [alpha-32P]TTP into poly[d(AT)] was observed. Nearest-neighbor analysis indicated that the analogue was not significantly incorporated into internal positions in the polymer. In DNA-sequencing reactions, the analogue caused chain termination at adensine residues, although termination was less uniform and less efficient than that with 2',3'-dideoxy-ATP. These experiments show that lin-benzoadenine can form a widened Watson-Crick base pair with thymine. They strongly suggest, though they do not prove, that the enzyme is able to attach the analogue to DNA.
通过对2-(β-D-呋喃核糖基)-8-(甲硫基)咪唑并[4,5-g]喹唑啉进行还原脱氧反应合成了2'-脱氧-lin-苯并腺苷。已通过化学和/或酶促方法制备了5'-单磷酸、5'-二磷酸和5'-三磷酸酯。发现5'-二磷酸是丙酮酸激酶磷酸化的底物，并在动力学测定中与各种天然和扩展底物进行了比较。当用大肠杆菌DNA聚合酶I在切口平移实验中测试2'-脱氧-lin-苯并腺苷5'-三磷酸时，观察到从[α-32P]TTP到聚[d(AT)]的32P掺入水平非常低。最近邻分析表明该类似物没有显著掺入聚合物的内部位置。在DNA测序反应中，该类似物导致腺嘌呤残基处的链终止，尽管终止不如使用2',3'-二脱氧-ATP时那么均匀和有效。这些实验表明lin-苯并腺嘌呤可以与胸腺嘧啶形成加宽的沃森-克里克碱基对。它们强烈暗示，尽管没有证明，但该酶能够将类似物连接到DNA上。
