Metal binding to DNA

Of course, and foremost, this concept applies to mispairing scenarios caused by metal binding to DNA and to pairing schemes in RNA involving noncomple-mentary bases, with one being metalated. 

Metal binding to DNA results in reduced/impaired DNA repair mechanisms, leading to mutagenesis... 

To put in perspective the binding of metal ions to ligand-modified nucleic acid duplexes, we summarize the conclusions of these reviews on metal binding to DNA duplexes and emphasize those conclusions that are relevant for the influence of metal coordination on the secondary structure of DNA. These studies have been the prologue of today s efforts to use DNA or its synthetic analogues as scaffold for transition metal ions. 

Scope of data. This chapter covers metal ion interactions with DNA, RNA and polynucleotides. A few related data involving oligonucleotides are included when necessary and appropriate. Oligomers when crystallized for X-ray analysis resemble polymers and are treated as such. The subject matter is limited to direct effects of metal binding, e.g. metal association constants and binding characteristics, metal binding effects on conformation, and metal-catalyzed depolymerization. There are of course many other phenomena that could be included, but are deemed unsuitable for tabulation. The effects of metal binding to DNA and RNA that involve interaction with proteins are covered only when the primary effect is on the nucleic acid moiety. 

This section contains association constants of metal binding to DNA, polydeoxynucleotides, and poly- ... 

Another way in which Pt could bind to DNA is through the formation of intercalation compounds. The parallel here is with the hydrocarbon carcinogens and the nucleic acid stains, the acridines. It has been shown that metal chelates will form this same type of jt-complex. For example, palladium oxinate will form exactly the same type of -complexes as anthracene (88). 

Trigonal ML3 metal complexes exist as optically active pairs. The complexes can show enantiomeric selective binding to DNA and in excited state quenching.<34) One of the optically active enantiomers of RuLj complexes binds more strongly to chiral DNA than does the other enantiomer. In luminescence quenching of racemic mixtures of rare earth complexes, resolved ML3 complexes stereoselectively quench one of the rare earth species over the other. 35-39 Such chiral recognition promises to be a useful fundamental and practical tool in spectroscopy and biochemistry. 

DNA mediated photoelectron transfer reactions have been demonstrated60 . Binding to DNA assists the electron transfer between the metal-centered donor-acceptor pairs. The increase in rate in the presence of DNA illustrates that reactions at a macromolecular surface may be faster than those in bulk homogeneous phase. These systems can provide models for the diffusion of molecules bound on biological macromolecular surfaces, for protein diffusion along DNA helices, and in considering the effect of medium, orientation and diffusion on electron transfer on macromolecular surfaces. 

Jaquet L, Kelly JM, Kirsch-De Mesmaeker A (1995) Photoadduct between tris(1,4,5,8-tetraazaphena nthrene)ruthenium(ll) and guanosine monophosphate - a model for a new covalent binding of metal complexes to DNA. J Chem Soc Chem Commun 913-914 Jay-Gerin J-P, Ferradini C (2000) A new estimate of the OFI radical yield at early times in the radiolysis of liquid water. Chem Phys Lett 317 388-391... 

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