事实上,除右手双螺旋结构外,还存在其他非经典DNA构象,如三链体DNA(triplex DNA)。三链体DNA是由单链DNA通过胡斯坦氢键(Hoogsteen hydrogen bonds)与双链DNA的大沟特异性结合形成的一种三链结构【2】。该结构在基因组中广泛分布,...
The specificity of triplexes relies in the formation of Hoogsteen hydrogen bonds between the third-strand bases and the purine bases of the duplex (Rajagopal and Feigon, 1989b; Soyfer and Potaman, 1996; Thuong and Hélène, 1993). Triplexes can be classified based on the composition and ...
Lieblein AL, Krämer M, Dreuw A, Fürtig B, Schwalbe H: Bonds in DNA i-motifs the nature of hydrogen bonds in cytidine…H + …cytidine DNA base pairs. Angew Chem Int Ed Engl 2012, 51: 4067–4070. View ArticleLieblein, A. L.; Kram̈ er, M.; Dreuw, A.; Fürtig, ...
To actually visualize the double-helical structure of DNA, researchers require special imaging technology, such as the X-ray diffraction used by Rosalind Franklin. However, it is possible to see chromosomes with a standard light microscope, as long as the chromosomes are in their most condensed fo...
The bases of each strand link together via hydrogen bonds. Adenine and Guanine are purines as they have two rings in their molecular structure. Thymine and Cytosine are pyrimidines as they only have one ring in their molecular structure. A purine will link with a pyrimidine. Adenine and thymi...
The bases on each strand are joined to the bases on the other strand with hydrogen bonds, but different bases have different chemical structures. Cytosine and thymine (and uracil in RNA) are pyrimidines, containing one ring. Adenine and guanine are purines, containing two rings. The pyrimidine...
DNA denaturation refers to the process in which the hydrogen bonds and van der Waals interactions that hold the double helix structure of DNA together are weakened, leading to the separation of the DNA strands. This can be induced by various agents such as heat, strong alkalis, urea, and for...
(suggested by Chargaff’s Rules). Thus, adenine and thymine are complementary base pairs, and cytosine and guanine are also complementary base pairs. The base pairs are stabilized by hydrogen bonds:adenine and thymine form two hydrogen bonds and cytosine and guanine form three hydrogen bonds.The ...
hydrogen bonds with the A3 nucleotide (2.7 and 3.0 Å, respectively). In parallel with Asn144 side chain lies the Arg148 guanidinium head group, which in turn forms two hydrogen with the G2 nucleotide (3.1 and 3.1 Å, respectively). Besides, in the region surrounding T1GAT4...
Three-stranded DNA in which single-stranded DNA hydrogen bonds into the major groove of purine-rich standard B-form DNA. Telomeres The ends of linear chromosomes, usually consisting of GC-rich repeated DNA, with guanines clustered in the strand that forms the 3′ end of the chromosome. The ...