A new modified thrombin binding aptamer containing a 50–50 inversion of polarity site
نویسندگان
چکیده
The solution structure of a new modified thrombin binding aptamer (TBA) containing a 50–50 inversion of polarity site, namely d( 0 GGT 0 0 TGGTGTGGTTGG0), is reported. NMR and CD spectroscopy, as well as molecular dynamic and mechanic calculations, have been used to characterize the 3D structure. The modified oligonucleotide is characterized by a chair-like structure consisting of two G-tetrads connected by three edge-wise TT, TGT and TT loops. d( 0 GGT 0 0 TGGTGTGGTTGG 0 ) is characterized by an unusual folding, being three strands parallel to each other and only one strand oriented in opposite manner. This led to an antianti-anti-syn and syn-syn-syn-anti arrangement of the Gs in the two tetrads. The thermal stability of the modified oligonucleotide is 4 C higher than the corresponding unmodified TBA. d( 0 GGT 0 0 TGGTGTGGTTGG 0 ) continues to display an anticoagulant activity, even if decreased with respect to the TBA.
منابع مشابه
A new modified thrombin binding aptamer containing a 5′–5′ inversion of polarity site
The solution structure of a new modified thrombin binding aptamer (TBA) containing a 5'-5' inversion of polarity site, namely d(3'GGT5'-5'TGGTGTGGTTGG3'), is reported. NMR and CD spectroscopy, as well as molecular dynamic and mechanic calculations, have been used to characterize the 3D structure. The modified oligonucleotide is characterized by a chair-like structure consisting of two G-tetrads...
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تاریخ انتشار 2006