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Results show that the conformational changes that mediate the active site assembly and metal binding by EcoRV endonuclease are modulated by the electrostatic effects in the DNA cleavage region of the enzyme. Kinetic and crystallographic analyses of the charged active site mutants reveal that site-specific mutations do not affect enzyme activity.

Analysis of DNA exposed to UV radiations at 254nm and 100 to 10,000 J m2 reveals the presence of three monomeric products, of which two are formamidopyrimidine derivatives, and the third is a pyrimidine derivative. These monomers act as substrates for base excision enzymes that repair oxidatively damaged DNA. The yield of the thymine derivative depends directly on intensity of UV radiation, while the quantity of the other derivatives obtained vary nonlinearly. Increased dosage of radiations also induces the formation of several other derivatives of purine and pyrimidine.

Relaxation data was obtained during the 13C-NMR spectra of three DNA oligonucleotide duplexes and was the basis of the 'model free' approach. Model free analysis provided such information as the effective internal correlation time, the terminal residue-ordered parameters and the optimized values for the entire correlation times.

The combining fluorescence anisotropy with fluorescence resonance energy transfer (FRET) measures, the complete catalytic cycle of EcoRV endonuclease. Binding, bending and cleavage of substrate oligonucleotide were monitored in real time anisotropy.

Research was conducted to examine the divalent metal dependence of site-specific DNA binding by EcoRV endonuclease. For short duplex oligodeoxynucleotides having the cognate DNA site, three cleavable noncognate sites and a fully nonspecific site, the binding constants were determined. Results provide strong evidence that measurements of DNA binding affinities for EcoRV should be conducted in the presence of divalent metal ions.