Nucleic acid, helical

Seeman, N.C., Rosenberg, J.M., Rich, A. Sequence-specific recognition of double helical nucleic acids by proteins. Proc. Natl. Acad. Sci. USA 73 804-809, 1976. 

Synthesis and application in molecular biology of double-helical nucleic acids with covalent-bonded chains 98UK274. 

Sticky-ends Complementary single-stranded tails projecting from otherwise double-helical nucleic acid molecules. 

Soyfer VN, Potaman VN (1995) Triple-helical nucleic acids. Springer, New York... 

Potaman, V.N. and Sinden, R.R. (1995) Stabilization of triple-helical nucleic acids by basic oligopeptides. Biochemistry, 34,14885-14892. 

Fig. 10.2 2D NMR spectrum of a double helical nucleic acid with corresponding experimental data.

The method today is mostly applicable to relatively small molecules of up to 15,000 Daltons. With higher field NMR spectrometers and with practical 3D NMR, 25-30,000 Daltons will generally approach the limit (early- to mid-1990s). Figure 10.2 shows the 2D NMR spectrum of a double helical nucleic acid (MW 7000) while a stereo pair of the structure is shown in Figure 10.3. 

Fig. 10.3 Stereo pair of the double helical nucleic acid, 2D NMR spectrum of which is shown in Figure 10.2.

V.N. Soyfer and V.N. Potaman, Triple-Helical Nucleic Acids (Springer. New York, 1995). 

Fig. 16.10. Schematic description of A-U base pairs found in crystals and in double helical nucleic acids. AU62 Watson-Crick A(JS2 reversed Watson-Crick AU32 Hoogsteen AU22 reversed Hoogsteen...

Hydration Motifs in Double Helical Nucleic Acids... 

At present, there are only a few cases known of sequence-specific hydration of double helical nucleic acids. With the availability of more crystal structure data, new information concerning sequence-specific hydration is expected. This kind of hydration can have an influence on the recognition of nucleic acids by proteins, and is therefore of great interest. 

Double-stranded helical nucleic acids in aqueous solution likewise exhibit very pronounced dielectric dispersion behaviour at fairly low frequendes. This was originally also interpreted on the basis of rotational orientation... 

The immunospecihcally purified antibodies have been particularly useful in physicochemical studies of the antibody-nucleic acid interaction for some purposes, the monovalent Fab fragments of the purified antibodies have been used. - The use of absorbed and purified antibodies also ensures the specificity of immunofluorescent and serological measurements of helical nucleic acids of a given class in the presence of other nucleic acid forms. 

Figure 37-19 Melting curve of double-helical nucleic acid. (Modified with permission from Piper MA, Unger ER Nucleic Add Probes A Primer for Potho/og/sts. Chicago, ASCP Press, 1989.)...

In this section we discuss the change that occur in the melting of DNA and RNA. The term melting is used to refer a thermally induced transition of a double-helical nucleic acid from an ordered double helix to a disordered state. Native RNA is usually single stranded, but it folds back on itself to form double helical sequences. Raman spectroscopy does not appear to be sensitive to the tertiary structure of RNA, but it can tell what fraction of the RNA is in double-helical form. ... 

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