posted on 2005-02-23, 00:00authored byEun Jeong Cho, Litao Yang, Matthew Levy, Andrew D. Ellington
An allosteric ribozyme (aptazyme) has been used to transduce the binding of a small organic analyte (ATP) into the ligation of a circular template for rolling circle amplification (RCA). An ATP-activated deoxyribozyme ligase was immobilized on a glass slide and, upon addition of ATP, catalyzed the ligation of a circular padlock probe. The ligated products could be directly amplified and visualized via RCA. The coupled reaction exhibited could detect as little as 1 μM of ATP and could discriminate against structurally similar nucleotides such as GTP, CTP, and UTP. Cooperative ATP activation of the deoxyribozyme was faithfully mimicked by RCA, yielding an amplified “switch” that was responsive to ATP concentration.