DNA另一种结构的一些含义。

Some implications of an alternative structure for DNA.

作者信息

Sasisekharan V, Pattabiraman N, Gupta G

出版信息

Proc Natl Acad Sci U S A. 1978 Sep;75(9):4092-6. doi: 10.1073/pnas.75.9.4092.

DOI:10.1073/pnas.75.9.4092

PMID:279899

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC336057/

Abstract

We have constructed a space-filling (Corey-Pauling-Koltun) model of an alternative structure for DNA. This structure is not a double helix, but consists of a pair of polynucleotide strands lying side by side and held together by Watson-Crick base pairing. Each of the two strands has alternating right- and left-handed helical segments approximately five base pairs in length. Sugar residues in alternating segments along a strand point in opposite directions. A structure slightly different from the present one proposed earlier by ourselves and another group and in which sugars in a strand all point in the same direction is ruled out. The present structure yields natural solutions to the problems of supercoiling of DNA and of strand separation during DNA replication. This model is energetically more favorable than the double helix.

摘要

我们构建了一种DNA替代结构的空间填充（科里-保林-科尔图恩）模型。这种结构不是双螺旋，而是由一对并排的多核苷酸链组成，并通过沃森-克里克碱基配对结合在一起。两条链中的每一条都有交替的右手和左手螺旋片段，长度约为五个碱基对。沿着一条链交替片段中的糖残基指向相反的方向。我们自己和另一组早些时候提出的一种与当前结构略有不同的结构被排除了，在那种结构中，一条链中的糖都指向同一个方向。当前结构为DNA超螺旋问题以及DNA复制过程中的链分离问题提供了自然的解决方案。这个模型在能量上比双螺旋更有利。