Synthesis and Characterization of the Native Anticodon Domain of <i>E. </i><i>c</i><i>oli</i> tRNA<sup>Lys</sup>: Simultaneous Incorporation of Modified Nucleosides mnm<sup>5</sup>s<sup>2</sup>U, t<sup>6</sup>A, and Pseudouridine Using Phosphoramidite Chemistry
作者:Mallikarjun Sundaram、Pamela F. Crain、Darrell R. Davis
DOI:10.1021/jo000338b
日期:2000.9.1
protecting groups suitable for automated RNA oligonucleotide synthesis. The 17 nucleotide anticodon stem-loop of E. coli tRNA(Lys) was then assembled from these synthons using phosphoramidite coupling chemistry. Coupling efficiencies for the two hypermodified nucleosides and for pseudouridine phosphoramidite were all greater than 98%. A mild deprotection scheme was developed to accommodate the highly functionalized
大肠杆菌tRNA(Lys)的反密码子结构域分别在位置34和37处包含超修饰的核苷mnm(5)s(2)U和t(6)A,以及在位置39处更常见的psi。这三个核苷酸中的一个代表自然界中最广泛修饰的RNA结构域之一。高度修饰的核苷mnm(5)s(2)U和t(6)A的2-氰乙基二异丙基亚磷酰胺分别带有适合于自动RNA寡核苷酸合成的保护基。然后使用亚磷酰胺偶联化学从这些合成子组装大肠杆菌tRNA(Lys)的17个核苷酸的反密码子茎环。两种超修饰核苷和假尿苷亚磷酰胺的偶联效率均大于98%。开发了温和的脱保护方案以容纳高度官能化的RNA。高偶联产率,温和的脱保护作用以及高效的HPLC纯化使我们能够从1微摩尔规模的RNA合成物中获得1. 8 mg的纯化RNA。我们有效的合成方案将允许对该独特的tRNA物种进行生物物理研究,其中已显示核苷修饰在密码子-反密码子识别,tRNA氨酰基合成酶识别和程序化核糖体移码