ATP-dependent allosteric DNA enzymes.
Effector-activated ribozymes that respond to small organic molecules have previously been generated by appending binding species (aptamers) to ribozymes. In order to determine if deoxyribozymes can similarly be activated by effector molecules, we have appended an anti-adenosine aptamer to a selected deoxyribozyme ligase. The resultant constructs are specifically activated by ATP. Optimization of the joining region resulted in ligases that are activated up to 460-fold by ATP. The selected deoxyribozyme catalyzes ligation largely via a templating mechanism. Effector activation is surprisingly achieved by suppression of the rate of the background, templated ligation reaction in the absence of the effector molecule, probably by misalignment of the oligonucleotide substrates. This novel allosteric mechanism has not previously been observed for nucleic-acid catalysts and is rare even in protein catalysts.
Levy
Matthew
M
Department of Chemistry and Biochemistry, Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
Ellington
Andrew D
AD
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000494:Allosteric Regulation / Q000187:drug effects*; D001483:Base Sequence; D002384:Catalysis / Q000187:drug effects; D021881:DNA, Catalytic / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015195:Drug Design; D004789:Enzyme Activation / Q000187:drug effects; D008025:Ligases; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000378:metabolism
D021881:DNA, Catalytic; D009838:Oligodeoxyribonucleotides; D000255:Adenosine Triphosphate; D008025:Ligases