BIOL 86 |
| RNA aptamers are prime candidates for biosensor applications because they possess high affinity and selectivity to target molecules. The ATP-binding RNA aptamer was modified by the substitution of 2-aminopurine (2AP), a fluorescent nucleotide, for adenosine at several positions. The fluorescence of 2AP is sensitive to stacking, making it an excellent probe for the binding of small molecules by RNA aptamers, an event often characterized by significant structural rearrangement. The 2AP modified aptamers have been studied by fluorescence titration, CD and melting temperature experiments. Interestingly, the substitution of 2AP for adenosine residues within stem regions removed from the site of ATP binding yielded mutant RNA aptamers that were still sensitive to ATP binding. Since the 2AP modified aptamers display a range of affinity for ATP (from 5 - 200 µM), one can envision using an array of 2AP modified aptamers in a biosensor chip for ATP. |
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Chemistry and Metabolism
4:30 PM-6:30 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster
Division of Biological Chemistry |