2-aminopurine (2-AP) is a fluorescent analog of adenine (6-aminopurine). The fluorescence of 2-AP ia quenched once it is incorporated into the base-stacked structure of dsDNA. However, if the base stacking or base pairing of DNA is locally perturbed, the fluorescence of 2-AP is enhanced. Therefore the intensity of fluorescence emissions by 2-AP molecules can be used to monitor perturbations in DNA structure caused by interactions between DNA and proteins, such as DNA polymerase, helicase, and methyl transferase.
Subjects: Genetics and Genomics.