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A mechanism involving two-metal ions and double Lewis-acid activation of the substrate, combined with leaving group stabilization is proposed, for a number of phosphoryltransfer enzymes, including the exonuclease subunit of DNA polymerase I. It is designed as a synthetic phosphoryl transfer catalyst the dicopper(II)macrocyclic complex LCu2 which is inspired by the active site structure of exonuclease subunit of DNA polymerase I enzyme.

A catalytic DNA-templated reaction of hydrolysis of an ester group in an N-modified peptide nucleic acid that is activated by a Cu(super 2+) complex-PNA is discovered and optimized. This reaction helps in developing a fully homogeneous and sensitive assay for sequence-specific DNA detection.

The rate of bis(p-nitrophenyl) phosphate (BNPP) hydrolysis by the ammonium-functionalized copper(II) complex ((Ln)Cu(NO3)4.2(H2O)) where n = 1,2 where L = (6,6'-(Me2HNCH2C=C)2bpy)2+ (L1) or (6,6'-(Me3NCH2C=C)2bpy)2+ and bpy = 2,2'-bipyridine in ethanol-water solution was investigated. The results revealed (L1)Cu to be 1,000 times more reactive than (L2)Cu and 2,900 times more reactive than (bpy)Cu for the cleavage of the phosphodiester. These are possibly due to the hydrogen bonding of the coordinated phosphodiester with -NMe2H+ which electrostatically activates metal-hydroxide attack on BNPP.

A stable, single-stranded DNA circle is smoothly formed from a linear precursor by metal Fe(sub 2+) assisted ring closure. With metal Zn(sub 2+), cyclization is reversible and a novel, complex type of allosteric regulation of hybridization is observed.

A study is conducted to identify the molecular design criteria and structural requirements for supramolecular allosteric systems and to indicate how strong allosteric effects can be achieved, corresponding to ON and OFF switching. The design of allosteric systems opens the possibility of controlling molecular function by external chemical input, as widely observed in biomolecular recognition and catalysis.

The potential of peptide nucleic acid (PNA) to act as an antisense and antigene agent, makes it similar to a DNA that has excellent binding affinity and sequence specificity toward oligonucleotides. The ability of Zn(super 2+), to increase the binding affinity of terminally modified PNA to DNA targets in vitro, is described for the first time.

A series of conjugates of peptide nucleic acids(PNA) and Zr(IV) complexes were prepared. The efficient artificial restriction enzyme found that PNA conjugate with a Zr(IV) complexes of tris(hydroxymethyl)-aminomethane, cleavage DNA targets sequence selectively in close proximity to the Zr(IV) complex.

It has been established that the dinuclear octaazamacrocyclic copper(II) complex LCu2 is the first nonenzymatic catalyst for the transesterification of simple alkyl phosphodiesters under mild conditions. It may act through a mechanism suggested for hydrolytic or alcoholytic phosphoryl transfer in various enzymes.