Nucleic acid interactions with ions

When a nucleic acid interacts with cations in aqueous solution, bound states form in the interfacial region of the macromolecule [10], These states are classified either as site bound or diffusely bound [9, 11-14], If the translational energy of the ions is unable to overcome the electrostatic forces between the ions and the nucleic acid, then the ions are viewed as trapped in a volume encasing the surface of the nucleic acid. These ions are site bound [9, 11, 13, 14]. 

Zubay, G., and P. Doty Nucleic acid interactions with metal ions and amino acids. Biochim. Biophys. Acta 29, 47 (1958). 

Bead pores are small relative to the nucleic acid molecule so that column interactions of the nucleic acid with the bead are on the surface of the bead. Polarity of the bead is adjusted so that nucleic acid interactions with the surface are controllable with ion pairing reagents. 

Polymetaphosphate 3 Polymorphonuclear leukocytes 26 Polynucleotide(s) 199s, 226-228. See also Nucleic acids, RNA, DNA hybridization 255 hydrazine reactions 254 interactions with ions 218 melting of 255 probes 255... 

The foundation of metal ion and nucleic acid interactions as a chemotherapy originate with the well known work of Rosenberg64 on platinum(II) complexes. Those containing chelating agents could destabilize nucleic acid structures by removing cations which promote the stability of histones. 

Nucleic acids are known to be responsible for the storage and transcription of genetic information in living cells and are involved in protein synthesis. Nucleic acids are polymers of nucleoside phosphates and hence negatively charged in neutral solutions. Nucleic acids interact strongly with metal ions. Such an interaction with metal ions helps to maintain the conformational stability of nucleic acids and their function. The formation of a complex... 

Why would people be interested in metal-nucleic acid interactions Perhaps because life as we know it is dependent on these interactions. Nucleic acids (DNA and RNA) are actually salts (or complexes) of metal ions from a chemical point of view. Therefore, it is difficult, if not impossible, to separate the behavior of DNA and RNA from their interactions with metal ions. We must also take into account specifically bound water molecules since they frequently mediate interactions between polynucleotides and metal ions. ... 

Interestingly, specific M +-nucleic acid interactions determined in solution for the hairpin ribozyme by spectroscopic and chemical interference methods were not later found in their X-ray crystal stmctures. Even more confusing were results of X-ray crystallography " and initial solution experiments, which both determined up to two, presumably functionally important Mg + ions in the catalytic center of the hammerhead ribozyme. However, as demonstrated recently in biochemical experiments in solution, neither of these ribozymes require either inner- or outer-sphere interactions with particular metal ions for catalysis. ... 

Fig. 40a, b. Zinc-finger DNA interactions [72] a interaction of the zinc finger in Fig. 28 with the bases of an oligonucleotide (note that the zinc ion is distant from the site of the protein-nucleic acid interaction, merely serving to define the folded structure of the finger), b the hydrogen bond pattern involved (see Fig. 22)... 

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