189145-17-3Relevant academic research and scientific papers
Kinetics and Mechanism of Facile and Selective Dephosphorylation of 2′-Phosphorylated and 2′-Thiophosphorylated Dinucleotides: Neighboring 3′-5′ Phoshodiester Promotes 2′-Dephosphorylation
Tsuruoka, Hiroyuki,Shohda, Koh-Ichiroh,Wada, Takeshi,Sekine, Mitsuo
, p. 2813 - 2822 (1997)
2′-Phosphorylated and 2′-thiophosphorylated dinucleotides U(2′-p)pU (1) and U(2′-ps)pU (2) were found to undergo facile 2′-specific dephosphorylation at 90°C in neutral aqueous solution to give UpU, and the first-order rate constants of these reactions were determined by HPLC. Particularly, U(2′-ps)pU (2, k = 1.38 ± 0.4 × 10-3 s-1, tcomp = 1 h) was cleanly dephosphorylated ca. 100 times more rapidly than U(2′-p)pU (1, k = 1.41 ± 0.05 × 10-5 s-1, tcomp = 72 h). Dephosphorylations of 1 and 2 were faster than those of thymidine 3′-phosphate (8) and thymidine 3′-thiophosphate (9), respectively. The kinetic data observed were independent of the 2′- or 3′-position of the phosphate group and the kind of base moiety. The neighboring 3′-5′ phosphodiester function most probably promotes the 2′-dephosphorylation efficiently. A branched trimer, U(2′-pU)pU (3), and related compounds having a substituent on the 2′-phosphoryl group, such as U(2′-pp-biotin)pU (4) and U(2′-ps-bimane)pU (5), were rather resistant to hydrolysis. The addition of divalent metal ions (Mg2+, Mn2+, Zn2+, Ca2+, Co2+, and Cd2+) remarkably decreased the rate of 2′-de(thio)phosphorylation of 1 or 2. Among these metal ions, Zn2+ most significantly inhibited the dephosphorylation. On the contrary, trivalent metal ions considerably accelerated the 2′-de(thio)phosphorylation of 1 or 2. The mechanism of 2′-dephosphorylation in the presence and absence of various metal ions is also discussed.
