Polynucleotide complex

In testing the possibility of proton transfer as a quenching mechanism of tyrosine in oligopeptide/polynucleotide complexes, Brun et a/.(102) compared the fluorescence emission spectra of the tyrosine and O-methyltyrosine tripeptides. They noted that, in the complex, the O-methyltyrosine tripeptide had a unique secondary emission near 410 nm. Whether this emission is related to that observed by Libertini and Small(94) is an important question. While one must consider the possibility that two tyrosine side chains could be converted to dityrosine, (96) which has a fluorescence at 400 nm, another intriguing possibility is ambient temperature tyrosine phosphorescence. This could happen if the tyrosine side chain is in a rigid, protective environment, very effectively shielded from collisions with quenchers, particularly oxygen. 

Deeble DJ, Schulz D, von Sonntag C (1986) Reactions of OH radicals with poly(U) in deoxygenated solutions sites of OH radical attack and the kinetics of base release. Int J Radiat Biol 49 915-926 Denk O, Washino K, Schnabel W (1983) OH radical-induced chemical reactions of polynucleotide complexes. Makromol Chem 184 165-173... 

Sakurai K, Iguchi R, Mizu M et al (2003) Polysaccharide-polynucleotide complexes. Part 7. Hydrogen-ion and salt concentration dependence of complexation between schizophyllan and single-stranded homo RNAs. Bioorg Chem 31(3) 216-226... 

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... 

Koumoto K, Mizu M, Sakurai K et al (2004) Polysaccharide/polynucleotide complexes. Part 6. Chem Biodivers l(3) 520-529... 

Langer [3] coupled 1,4-butanediol diacrylate with poly(A, A -dimethylethyl-enediamine), (III), piperazine, and 4,4 -trimethylenedipiperidine to prepare poly(p-amino esters) that were particularly suited for the delivery of polynucleotides. Nanoparticles containing polymer/polynucleotide complexes were also prepared. Hubbell [4] and Zhao [5] prepared polymeric biomaterials by the nucleophilic addition of cysteine, (IV), and polyethylenimine, (V), respectively, to cx,p-unsaturated macromolecular diacrylates. 

The inhibitions described above occurred only when the analog and polynucleotide contained complementary bases. These combinations are not the only ones in which the interaction can occur, e.g., affinity methods detect some interaction between the non-complementary poly-9-vinyladenine and polyadenylate Apparently, such complexes are too unstable to affect the enzymatic reactions nevertheless, extensive modification of the analog can increase the stability of the polymer-polynucleotide complex to the point where such a polymer can effectively inhibit the reaction. Thus, omisssion of the amino group from poly-9-vinyladenine leads to poly-9-vinylpurine and the latter polymer inhibits the reverse transcription of polyadenylate and polyuridylate The introduction of a dimethylamino group in place of the amino group of poly-9-vinyladenine abolMies all of its inhibitory effects All these effects can be correlated with the ability of polymers to form complexes with templates. 

The hybridization potential of a probe remains intact after mercuration. Sulfhydryl compounds bind strongly to mercurated nucleic acids and a variety of sulfhydryl-(primary label) ligands can be introduced in the complex after hybridization. Simpson (1961) observed a typical association constant of mercury for sulfhydryl compounds of 10 M but the mercury-sulfhydryl bond in polynucleotide complexes may be less stable (Hopman et al., 1986a). An interesting application... 

Synthetic polynucleotide complexes have been shown to be effective immune response modulators in animals and man (Braun et al. 1971, Johnson 1979). The polynucleotides are formed foUowing the action of an enzyme, polynucleotide phosphor-ylase on the synthetic mononucleotide diphosphates. Complexing takes place following the mixing of polymers composed of opposite base pairs. Two have been utilised, polyinosinic acid complexed with polycytidylic acid (poly I poly C) and polyad-enylic acid complexed with polyuridylic acid (poly A poly U). The single strands mononucleotides are ineffective. 

Field, A.K., Tytell, A.A., Lampson, G.P., and Hilleman, M.R., 1967, Inducers of interferon and host resistance. II. Multistranded synthetic polynucleotide complexes, Proc Natl Acad Sci USA,... 

Marionneau C, Abriel H (2015) Regulation of the cardiac Na + channel NaVl.5 by post-translational modifications. J Mol Cell Cardiol 82 36-47 Meneksedag-Erol D, Tang T, Uludag H (2014) Molecular modeling of polynucleotide complexes. Biomaterials 35 7068-7076... 

IMMUN Immunochemical measurements was determined from a plot of complement-fixing reactivity of a polynucleotide complex vs. temperature (244) such plots were very similar in shape to the absorbance-tenq)erature profiles,... 

Many exotic duplexes, with modifications on the base and/or the sugar have been included. No attempt has been made, however, to deal with random copolymers and partially modified polynucleotides. Nor has there been an attempt to cover the numerous studies on nucleoside (nucleotide) - polynucleotide complexes [74tl] and the analogous oligonucleotide work [74t2]. The latter field is in full fling and new data appear every week. 

Like double-stranded DNA, synthetic polynucleotide complexes containing complementary bases show cooperative melting curves, i.e., the property studied (UV absorption, optical activity, viscosity, etc.) shows a sharp transition at a specific temperature. This Tm depends on ionic strength and, to a certain degree, on pH. If the temperature is increased above the Tm, however, a further continuous variation in the property studied will be observed. It is only in recent years that an understanding of such noncooperative phenomena is emerging. Here the studies of oligomers by CD and NMR were of critical importance. 

The four-stranded poly(l) structure surprisingly shows a 2 -endo puckering in contrast with all other ribopolynucleo-tldes studied so far (Table 6.1) and also in contrast with the 3 -endo puckering of the three-stranded polynucleotide complexes. 

FIGURE 6.8. Ionic strength dependence of A- and U (or T)-containing polynucleotide complexes. 

Arnott s group is currently studying all these polynucleotide complexes by X-ray fiber diffraction, and the results will clarify some ambiguities. Thus, poly(dG) poly(dC) in fibers was found to be preferentially in the A form. The alternating polymers poly(dA-dT) and poly(dG-dC) show a rather unusual D form, with eight base pairs per turn (Table 6.1). Although the D- A transition is observed at low relative humidities, the A form is metastable, and the transition is never complete, returning rapidly to the D form (27). 

Some other polynucleotide complexes. Polyxanthylic acid [poly(X)l forms complexes of various stoichiometries (1 1, 1 2, 2 1) with poly(U) and/or poly(l) (30). 

On the other hand, certain new results have been included, despite the limited comprehension we have of them. Thfs was done to demonstrate the "possibilities" of nucleic acids, their fine structure, and their future. For this reason, repeating sequences, restriction enzymes, and unusual polynucleotide complexes are treated. 

Nucleic Acids - The use of nucleic acids as adjuvants to the immune response was first indicated in the demonstration of a restorative capacity of nucleic acid-rich tissues in animals rendered immunodeficient following x-irradiation . Their ability to act as adjuvants to the normal immune response to unrelated antigens has also been documented and shown to be attributable to low molecular weight oligonucleotides. Extended study over the past 5 years has shown the more well-defined polynucleotide complexes (poly A U and poly I C) to be powerful adjuvants to many antigens... 

III. Experimentally-Induced Antisynthetic-Polynucleotide Complex Antibodies. Role of the Conformation of the Immimogen 1. General Considerations... 

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