The generality of DNA-templated synthesis as a basis for evolving non-natural small molecules
The generality of DNA-templated synthesis as a basis for evolving non-natural small molecules
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DOI：
10.1021/ja015873n
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发表时间：
2001-07-18
影响因子：
15
通讯作者：
Liu, DR
中科院分区：
文献类型：
--
作者：
Gartner, ZJ;Liu, DR
尽管蛋白质和核酸的化学功能有限，但它们主导着许多复杂化学问题的解决方案，因为它们可以通过多样化、选择和放大的迭代循环而进化。研究人员已经广泛地证明，最初缺乏所需活性的蛋白质和核酸可以被突变、扩增和重新选择，以提供具有极大增强性质的进化分子。1我们有兴趣通过开发将DNA转化为合成结构的方法来创建可扩增和可进化的非天然小分子文库。实现这一目标需要使用DNA来指导化学反应序列--具体地说，以一种比迄今报道的更普遍的方式。研究人员此前已经证明，核酸模板能够促进相邻退火寡核苷酸的偶联，形成核酸和核酸类似物。2我们假设DNA模板合成提供的邻近效应可以用来在一锅平行反应中产生结构上与DNA骨架无关的合成小分子的文库。我们测试了两种DNA结构支持溶液相DNA模板合成的能力(图1)。含有亲电性马来酰亚胺基团的发夹(H)和螺旋末端(E)模板都能有效地与连接到互补DNA寡核苷酸的硫醇试剂在25℃下反应几分钟生成硫醚产物。DNA模板反应速率(KAPP)∼105M-1 S-1)对于H和E构型相似，尽管它们的反应基团的相对取向有显著差异。相反，当使用包含序列错配的试剂时，或当使用用过量β-巯基乙醇预淬火的模板时，没有观察到任何产物(图1)。因此，H和E模板都支持序列特异的DNA模板将硫醇加成到马来酰亚胺上，即使所得产物的结构与天然磷酸二酯主链的结构明显不同。在该反应条件下(pH 7.5，25℃，250 mM氯化钠，60 nm模板和试剂)很少或没有非模板化的分子间反应产物。
Despite their limited chemical functionality, proteins and nucleic acids dominate the solutions to many complex chemical problems because they can be evolved through iterated cycles of diversification, selection, and amplification. Researchers have demonstrated extensively that proteins and nucleic acids initially lacking desired activities can be mutated, amplified, and reselected to afford evolved molecules with greatly enhanced properties. 1 We are interested in creating amplifiable and evolvable libraries of non-natural small molecules by developing methods to translate DNA into synthetic structures. Achieving this goal requires using DNA to direct chemical reactions sequence-specifically in a manner much more general than has been reported thus far. Researchers have previously demonstrated the ability of nucleic acid templates to promote the coupling of adjacently annealed oligonucleotides to form nucleic acids and nucleic acid analogues. 2 We hypothesized that the proximity effect provided by DNA-templated synthesis can be used to generate libraries of synthetic small molecules unrelated in structure to the DNA backbone in one-pot, parallel reactions.We examined the ability of two DNA architectures to support solution-phase DNA-templated synthesis (Figure 1). Both hairpin (H) and end-of-helix (E) templates bearing electrophilic maleimide groups reacted efficiently with one equivalent of thiol reagent linked to a complementary DNA oligonucleotide to yield the thioether product in minutes at 25 C. DNA-templated reaction rates (kapp)∼ 105 M-1 s-1) were similar for H and E architectures despite significant differences in the relative orientation of their reactive groups. In contrast, no product was observed when using reagents containing sequence mismatches, or when using templates pre-quenched with excess β-mercaptoethanol (Figure 1). Both H and E templates therefore support the sequence-specific DNA-templated addition of a thiol to a maleimide even though the structures of the resulting products differ markedly from the structure of the natural phosphodiester backbone. Little or no nontemplated intermolecular reaction products are produced under the reaction conditions (pH 7.5, 25 C, 250 mM NaCl, 60 nM template and reagent).