Kinetic studies on the interaction of gold (III) with nucleic acids. IV. RNA-Au (III) system.
The kinetics of the interaction of Au(III) with whole yeast RNA has been studied using UV-spectrophotometry. The reaction is second order with respect to the nucleotide unit of RNA and first order with respect to Au(III) in the respective stoichiometry of 2 : 1. The effects of initial composition, temperature, ionic strength, pH and chloride ion on the kinetics have been studied. Activation energy is found to be 11.5 kcal/mol. Effect of ionic strength indicates that both the positively charged and neutral species of Au(III) take part in the rate limiting step, the former being dominant at low ionic strength. A plausible mechanism has been proposed which involves the interaction of two nucleotide units of RNA with one species of Au(III) in the rate limiting step.
Kinetic studies on the interaction of gold (III) with nucleic acids. IV. RNA-Au (III) system. The kinetics of the interaction of Au(III) with whole yeast RNA has been studied using UV-spectrophotometry. The reaction is second order with respect to the nucleotide unit of RNA and first order with respect to Au(III) in the respective stoichiometry of 2 : 1. The effects of initial composition, temperature, ionic strength, pH and chloride ion on the kinetics have been studied. Activation energy is found to be 11.5 kcal/mol. Effect of ionic strength indicates that both the positively charged and neutral species of Au(III) take part in the rate limiting step, the former being dominant at low ionic strength. A plausible mechanism has been proposed which involves the interaction of two nucleotide units of RNA with one species of Au(III) in the rate limiting step.