The kinetics of ligand binding by an adenine-sensing riboswitch

The stability of the aptamer domain of the pbuE riboswitch is examined and the thermodynamic and kinetic properties of adenine, 2-aminopurine and 2,6-diaminopurine ligand binding are determined. The findings support the hypothesis that many riboswitches rely on the kinetics of ligand binding and the speed of RNA transcription to establish the concentration of metabolite needed to trigger riboswitch function.