Abstract:
:Molecular beacons are DNA probes that form a stem-and-loop structure and possess an internally quenched fluorophore. When they bind to complementary nucleic acids, they undergo a conformational transition that switches on their fluorescence. These probes recognize their targets with higher specificity than probes that cannot form a hairpin stem, and they easily discriminate targets that differ from one another by only a single nucleotide. Our results show that molecular beacons can exist in three different states: bound to a target, free in the form of a hairpin structure, and free in the form of a random coil. Thermodynamic analysis of the transitions between these states reveals that enhanced specificity is a general feature of conformationally constrained probes.
journal_name
Proc Natl Acad Sci U S Aauthors
Bonnet G,Tyagi S,Libchaber A,Kramer FRdoi
10.1073/pnas.96.11.6171keywords:
subject
Has Abstractpub_date
1999-05-25 00:00:00pages
6171-6issue
11eissn
0027-8424issn
1091-6490journal_volume
96pub_type
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