'Molecular break lights' detect DNR-cleaving agents

Researchers by the biotech and pharmaceutical industry collaborators have devised a technique which is based on 'molecular break lights' hairpin-shaped DNAs from which a fragment breaks off and lights up in the presence of a DNA-cleaving agent. Enediynes are small organic compounds that exhibit antibiotic and anticancer effects and have a mechanism of action involving cleavage of single-stranded or double-stranded DNA. Although the mechanism by which enediynes cleave DNA has been studied extensively by numerous groups, a continuous assay for enediyneinduced DNA cutting has not been available. A DNA sequence susceptible to cleavage by a specific DNA cleaving agent is designed into the break light's stem. The fluorescent group and quencher are adjacent to each other in the break light, preventing the fluorescent group from lighting up.