Catalytic beacons

Liu J, Lu Y (2007) A DNAzyme catalytic beacon sensor for paramagnetic Cu2+ ions in aqueous solution with high sensitivity and selectivity. J Am Chem Soc 129 9838-9839... 

Liu J, Brown AK, Meng X et al (2007) A catalytic beacon sensor for uranium with parts-per-trillion sensitivity and millionfold selectivity. Proc Natl Acad Sci USA 104 2056-2061... 

In an elegant approach toward DNA detection, Willner and colleagues introduced the use of catalytic beacons.Their method is illustrated in Figure 41. The thrombin protein was covalently modified with an oligonucleotide containing the TBA sequence.In the absence of a complementary DNA strand the appended TBA sequence folds into a G-quadruplex and blocks the enzyme s active site. Addition of a complementary DNA strand unfolds the G-quadruplex, resulting in substrate access to the thrombin s active site. Hydrolysis of a fluorophore-labeled peptide then results in a readily detectable optical signal. 

Liu, J. W., Brown, A. K., Meng, X. L., Cropek, D. M., Istok, J. D., Watson, D. B., Lu, Y. (2007b). A catalytic beacon sensor for uranium with parts-per-trillion sensitivity and millionfold selectivity. Proc Natl Acad Sci USA 104, 2056-2061. 

Stojanovic, M. N., de Prada, P., Landry, D. W. (2001b). Catalytic molecular beacons. ChemBioChem 2, 411-415. 

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