Renaturation of bacteriophage phiX174 DNA-RNA hybrid: RNA length effect and nucleation rate constant

A one to one RNA-DNA hybrid was synthesized using bacteriophage φX174 DNA as a template for the Escherichia coli RNA polymerase system. The renaturation rate for the hybrid was found to vary as the square root of the molecular weight of the RNA. The RNA molecular weights were determined using a standardized dimethylsulfoxide, cesium sulfate equilibrium density gradient. The optimum nucleation rate constant for the renaturation of the hybrid in 0.4 m-sodium chloride was found to be 1.3 × 10⁵, as compared with to 1.7 × 10⁵ for DNA renaturation.