01118nas a2200181   4500008004100000245008400041210006900125260000800194300001400202490000700216520050000223100002000723700002000743700001800763700002400781700002600805856010500831       2018                        eng d00aFavorable 2 '-substitution in the loop region of a thrombin-binding DNA aptamer0 aFavorable 2 substitution in the loop region of a thrombinbinding  cJUN  a1765-17680 v283 aSimple 2'-OMe-chemical modification in the loop region of the 15mer G-rich DNA sequence GGTTGGTGTGGTTGG is reported. The G-quadruplex structure of this thrombin-binding aptamer (TBA), is stabilized by single modifications (T -> 2'-OMe-U), depending on the position of the modification. The structural stability also renders significantly increased inhibition of thrombin-induced fibrin polymerization, a process closely associated with blood-clotting. (C) 2018 Elsevier Ltd. All rights reserved.1 aAwachat, Ragini1 aWagh, Atish, A.1 aAher, Manisha1 aFernandes, Moneesha1 aKumar, Vaijayanti, A.  uhttps://library.ncl.res.in/content/favorable-2-substitution-loop-region-thrombin-binding-dna-aptamer01475nas a2200217   4500008004100000022001400041245014500055210006900200260000900269300001600278490000600294520064300300653002700943653003000970653002201000653002901022653003001051100002001081700002401101856013201125       2019                        eng d  a2365-654900a2 `-5 `-Isomerically linked thrombin-binding aptamer (isoTBA) forms a stable unimolecular parallel G-quadruplex in the presence of Sr2+ Ions0 a2 5 Isomerically linked thrombinbinding aptamer isoTBA forms a s  cSEP   a10668-106730 v43 a<p>The ability of the isomeri 2 `-5 `-phosphodiester-linked thrombin-binding DNA aptamer pentadecamer G(2)T(2)G(2)TGTG(2)T(2)G(2) (isoTBA), to fold into G-quadruplex structures in the presence of different mono- and divalent cations is reported. Strikingly, Sr2+ ions cause isoTBA to fold into a stable parallel unimolecular G-quadruplex, in contrast to the antiparallel unimolecular G-quadruplex fold observed in the presence of K+. IsoTBA being advantageously more stable than TBA to nuclease degradation, may thus be useful in the selective detection of Sr2+ ions, which it can sense with a detection limit of similar to 55 mu M.</p>
10a2 `-5 `-phosphodiester10aparallel DNA G-quadruplex10astrontium binding10athrombin-binding aptamer10aunimolecular G-quadruplex1 aWagh, Atish, A.1 aFernandes, Moneesha  uhttps://library.ncl.res.in/content/2-5-isomerically-linked-thrombin-binding-aptamer-isotba-forms-stable-unimolecular-parallel-g01427nas a2200229   4500008004100000022001400041245012300055210006900178260000900247300001600256490000600272520062400278653001300902653001800915653002700933653001900960653002300979100002001002700002101022700002401043856013001067       2021                        eng d  a2365-654900aReplacement of loop residues in TBA by an abasic ethylene glycol spacer: effect on stability, structure and function**0 aReplacement of loop residues in TBA by an abasic ethylene glycol  cOCT   a10648-106500 v63 aThis article describes the synthesis of ethyleneglycol (E) phosphoramidite and its incorporation into the thrombin binding aptamer (TBA) sequence at loop positions. Circular dichroism (CD) study revealed no major disturbances in the secondary structure of TBA by the abasic E unit and the derived oligomers exhibited a typical antiparallel chair-like conformation similar to that of TBA. UV and CD spectroscopy, together with anti-coagulation and HPLC studies revealed that although nuclease stability was enhanced, and anti-coagulation reasonably good, the thermal stability of the quadruplexes was adversely affected.10aaptamers10aclotting time10aethylene glycol spacer10aG-quadruplexes10anuclease stability1 aWagh, Atish, A.1 aGhalawat, Monika1 aFernandes, Moneesha  uhttps://library.ncl.res.in/content/replacement-loop-residues-tba-abasic-ethylene-glycol-spacer-effect-stability-structure-and