NMR study on the impact of metal ion binding and deoxynucleotide substitution upon local structure and stability of a small ribozyme

FEBS Letters

Limmer, Stefan¹  Vogtherr, Martin¹ 

[1] Laboratorium für Biochemie der Universität Bayreuth, D-95440 Bayreuth, Germany

关键词: Nuclear magnetic resonance;    RNA;    Ribozyme;    Metal ion;   

DOI  :  10.1016/S0014-5793(98)00906-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have studied a very small ribozyme described earlier which requires the presence of soft metal ions like manganese or cadmium. It consists of only three uridines as ribozyme, cleaving the sequence 5′-GAAA-3′ after the guanosine. We have set out to characterize the metal ion binding in this system by NMR spectroscopy and the impact of the ribose 2′-OH group of the cleavable nucleotide upon local strucure. NMR results indicate a high degree of regularity and order in the pyrimidine-rich ribozyme strand, and high flexibility within the purine-rich substrate. The guanosine 2′-hydroxy group adjacent to the cleavage site was found to have a profound effect upon the structure, apparently destabilizing a stacked arrangement. Metal ions were found to bind in a rather unspecific way, however, in the presence of higher amounts of divalent ions a preference in the vicinity of the cleavage site could be observed. ¹¹³Cd NMR spectra suggest a specific binding of Cd²⁺ ions to the RNA.

【 授权许可】

Unknown