Suppr超能文献

在酸性pH条件下,由等摩尔比的同型嘌呤和同型嘧啶DNA链形成的三链复合物的核磁共振表征。

NMR characterisation of a triple stranded complex formed by homo-purine and homo-pyrimidine DNA strands at 1:1 molar ratio and acidic pH.

作者信息

Bhaumik S R, Chary K V, Govil G, Liu K, Miles H T

机构信息

Chemical Physics Group, Tata Institute of Fundamental Research, Bombay, India.

出版信息

Nucleic Acids Res. 1995 Oct 25;23(20):4116-21. doi: 10.1093/nar/23.20.4116.

Abstract

Homo-purine (d-TGAGGAAAGAAGGT) and homo-pyrimidine (d-CTCCTTTCTTCC) oligomers have been designed such that they are complementary in parallel orientation. When mixed in a 1:1 molar ratio, the system adopts an antiparallel duplex at neutral pH with three mismatched base pairs. On lowering the pH below 5.5, a new complex is formed. The NMR results show the coexistence of a intermolecular pyrimidine.purine:pyrimidine DNA triplex and a single stranded oligopurine at this pH. The triplex is stabilized by five T.A:T, four C+.G:C and two mismatched triads, namely, C+.G-T and T.A-C. This triplex is further stabilized by a Hoogsteen C+.G base-pair on one end. Temperature dependence of the imino proton resonances reveals that the triplex dissociates directly into single strands around 55 degrees C, without duplex intermediates. Parallel duplexes are not formed under any of the conditions employed in this study.

摘要

同型嘌呤(d-TGAGGAAAGAAGGT)和同型嘧啶(d-CTCCTTTCTTCC)寡聚物被设计成在平行方向上互补。当以1:1摩尔比混合时,该体系在中性pH下形成具有三个错配碱基对的反平行双链体。当pH降至5.5以下时,会形成一种新的复合物。核磁共振结果表明,在此pH下,分子间嘧啶·嘌呤:嘧啶DNA三链体和单链寡嘌呤共存。该三链体由五个T.A:T、四个C⁺.G:C和两个错配三联体(即C⁺.G-T和T.A-C)稳定。该三链体在一端还由一个Hoogsteen C⁺.G碱基对进一步稳定。亚氨基质子共振的温度依赖性表明,该三链体在55摄氏度左右直接解离为单链,没有双链中间体。在本研究采用的任何条件下都不会形成平行双链体。

相似文献

引用本文的文献

1
Non-canonical DNA structures: Diversity and disease association.非规范DNA结构:多样性与疾病关联
Front Genet. 2022 Sep 5;13:959258. doi: 10.3389/fgene.2022.959258. eCollection 2022.
4
Structural properties of g,t-parallel duplexes.g,t-平行双链体的结构特性。
J Nucleic Acids. 2010 Feb 21;2010:763658. doi: 10.4061/2010/763658.

本文引用的文献

3
H-DNA and related structures.H-DNA及相关结构。
Annu Rev Biophys Biomol Struct. 1994;23:541-76. doi: 10.1146/annurev.bb.23.060194.002545.
10
Intramolecular DNA triplexes in supercoiled plasmids.超螺旋质粒中的分子内DNA三链体
Proc Natl Acad Sci U S A. 1988 Sep;85(17):6292-6. doi: 10.1073/pnas.85.17.6292.

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验