Complementary polynucleotide

FIGURE 1.5 The DNA double helix. Two complementary polynucleotide chains running in opposite directions can pair through hydrogen bonding between their nitrogenous bases. Their complementary nucleotide sequences give rise to structural complementarity. 

Molecules of DNA consist of two complementary polynucleotide strands held together by hydrogen bonds between heterocyclic bases on the different strands and coiled into a double helix. Adenine and thymine form hydrogen bonds to each other, as do cytosine and guanine. 

Figure 3.6 (a) DNA structure. The two complementary polynucleotide strands in DNA are antiparallel to each... 

Figure 4.4 OrgeFs template-directed oligomerization. The main process in template-directed oligomerization of mononucleotides acmally occurs at the dimer or trimer level. When an activated mononucleotide is allowed to react in the presence of a complementary polynucleotide template, dimers are first formed in a non-catalyzed phase of the reaction they then bind to the template and are ligated and extended. (Adapted from Schwarz, 1998.)...

In A- or B-form DNA. two self-complementary polynucleotide strands associate with one another to form a right-handed double helix. The two polynucleotide chains arc antiparallcl. 

Sakurai K, Mizu M, Shinkai S (2001) Polysaccharide-polynucleotide complexes. 2. Complementary polynucleotide mimic behavior of a natural polysaccharide schizophyllan in the macromolecular comple with a single strand RNA poly(C). Biomacromolecules 2 641-650... 

The antisense approach to pharmaceuticals is conceptually attractive and powerful. If a protein target and its sequence are known, then the sequence of the corresponding mRNA will also be largely known. If the exact mRNA sequence can be determined, then a complementary polynucleotide may be prepared to form a duplex. Longer complementary antisense strands give a more stable duplex. 

In 1953, James D. Watson and Francis C. Crick used X-ray diffraction patterns of DNA fibers to determine the molecular structure and conformation of DNA. They found that DNA contains two complementary polynucleotide chains held together by hydrogen... 

Motifs of this category are found in the major and minor grooves, at the sugars, and at the phosphates. The water molecules can bridge functional atoms in the same (intra) nucleotide such as purine N(7) with 0(6)/N(6) groups or thymine 0(4) with the C(5) methyl group, or they can occur between different (inter) nucleotides belonging to the same or to complementary polynucleotide strands denoted intra- and interstrand respectively in Thble 24.6. 

Metal ion-binding modes, that compete with H-bonds for the donor and acceptor atoms of nucleic acids, normally destabilize the base pairs or prevent their formation, and thus promote melting (dissociation) of DNA at elevated temperatures. However, some of these metal ions, for example, Cu +, Mn + and AP+, can also promote renaturation of the dissociated DNA strands upon cooling presumably via cross-linking between complementary polynucleotide strands. ... 

In the first type the imidazole rings point roughly in the same direction as in purine and guanine. The second type has the imidazole rings of adjacent bases stacked in opposite directions as in guanosine dihydrate and in interstrand stacking between purines of complementary polynucleotide strands. 

Poly(7-deazaguanylic acid) has been prepared by polymerization of 7-deaza-guanosine 5 -diphosphate using polynucleotide phosphorylase from Micrococcus luteus, and its ability to form duplexes with complementary polynucleotides compared with that of poly(G). It is cleaved by ribonuclease T1 and also by nuclease SI, showing that unlike poly(G), it forms no selfstructure in aqueous solution. ... 

In 1953, James D. Watson and Francis C. Crick used X-ray diffraction patterns of DNA fibers to determine the molecular structure and conformation of DNA. They found that DNA contains two complementary polynucleotide chains held together by hydrogen bonds between the paired bases. Figure 23-26 shows a portion of the double strand of DNA, with each base paired with its complement. The two strands are antiparallel One strand is arranged 3 5 from left to right, while the other runs in the opposite direction, 5 3 from left to right... 

H was mixed with the complementary polynucleotide poly(A) - formation of a unique helical supramolecular structure [69]. 

During DNA replication, the two strands presumably unwind, and each strand serves as a template for the biosynthesis of a complementary polynucleotide chain. Such a semiconservative mechanism of replication finds support in two types of experimental evidence studies involving the separation of the two DNA strands during replication, and the mechanism of DNA synthesis in vitro. 

Complementary polynucleotide strands can be separated in alkaline CS2SO4 or CsCI gradients (6,17) (Fig. 2.4). 

FIGURE 6.4. Continuous variation experiment (Job plot) or mixing curve between two complementary polynucleotides, here poly(A) and poly(U). Note that the shapes of the curves are quite different at different wavelengths. (After Ref. 16.)... 

Another investigation (Marushide and Bonner, 1966) showed that chromatin isolated from the liver possessed about one-fifth of the activity of deproteinized DNA in relation to RNA-polymerase RNA synthesis. The factor responsible for this decreased activity was the chromatin histones. RNA synthesized on purified DNA consisted of complementary polynucleotides and was similar in its nucleotide composition to the DNA. RNA synthesized by chromatin consisted of noncomplementary molecules differing from total DNA in their nucleotide composition. On this basis, these workers claim that histones inhibit (close) specific zones in liver chromatin. 

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