Details

Autor(en) / Beteiligte

• Sigel, Roland K. O
• Sigel, Helmut
• Sigel, Astrid

Titel

Complex Formation of Nickel(II) with Sugar Residues, Nucleobases, Phosphates, Nucleotides, and Nucleic Acids

Ist Teil von

• Nickel and Its Surprising Impact in Nature, 2007, p.109-180

Ort / Verlag

Chichester, UK: John Wiley & Sons, Ltd

Erscheinungsjahr

2007

Link zum Volltext

Quelle

Wiley Online Library All Obooks

Beschreibungen/Notizen

• This chapter gives an overview on the diverse interactions between nickel(II) and nucleic acids and their constituents. In this context nickel always occurs in the oxidation state +II. In order to describe the specific properties of the various Ni(II) species often those of related metal ions are included in the present review for comparison. When considering only sugar moieties, the interaction between Ni(II) and the hydroxyl groups is very weak, and thus occurs only under very favored circumstances, i.e., when another primary binding site facilitates such an interaction. The binding may become more intense after deprotonation of a hydroxyl group at high pH. Among the common nucleobase moieties or nucleosides the guanine residue forms the most stable complexes with Ni(II); those of adenine or cytosine residues are rather weak. As soon as a phosphate group is present, as in nucleotides, this group becomes the primary binding site. Nevertheless, with purine‐nucleotides macrochelate formation involving N7 takes place and the corresponding intramolecular equilibria are described and the various isomers quantified. Such intramolecular interactions are not observed with pyrimidines because in the anti conformation, the possible binding site N3 is directed away from the phosphate‐coordinating Ni(II). In general, also outersphere complexes can play an important role; in case of phosphates their importance decreases with increasing charge meaning that innersphere species dominate. In nucleic acids the preferential binding sites of Ni(II) are guanine residues, but in some instances also an interaction with phosphate‐diester bridges was observed. Included into this review are also Ni(II) complexes of some less common nucleotides as well as nucleotide derivatives and analogs. The importance of mixed ligand complexes involving nucleotides is shortly emphasized (including those with common buffers) and in several instances isomeric equilibria are considered. Finally, some of the open questions regarding the interactions of Ni(II) with nucleic acids and their constituents are summarized.