锰（II）作为转运核糖核酸三级结构的顺磁探针。

Manganese(II) as a paramagnetic probe of the tertiary structure of transfer RNA.

作者信息

Chao Y Y, Kearns D R

出版信息

Biochim Biophys Acta. 1977 Jul 5;477(1):20-7. doi: 10.1016/0005-2787(77)90157-5.

Abstract

The effect of manganese on both the low field (10--15 ppm) and the high field (o--3 ppm) NMR spectra of unfractionated tRNA and yeast tRNAPhe has been investigated. Trace amounts of Mn2+ cause selective broadening of resonances which are assigned to specific tertiary interactions. The order in which resonances broaden is the same as the order in which they are stabilized by the addition of magnesium, namely s4U8 - A14, U33 and A58 - T54. From this we conclude that three of the strong binding sites probably are the same for both Mn2+ and Mg2+, and that these sites are located close to the tertiary interactions which are stabilized by the strongly bound metals. The broadening data, taken in conjunction with published X-ray data on yeast tRNAPhe, permit us to suggest some plausible locations for the strong binding sites.

摘要

研究了锰对未分级的转运核糖核酸（tRNA）和酵母苯丙氨酸tRNA的低场（10 - 15 ppm）和高场（0 - 3 ppm）核磁共振（NMR）谱的影响。痕量的Mn²⁺会导致特定共振峰选择性变宽，这些共振峰与特定的三级相互作用相关。共振峰变宽的顺序与加入镁后它们被稳定的顺序相同，即s⁴U⁸ - A¹⁴、U³³和A⁵⁸ - T⁵⁴。由此我们得出结论，对于Mn²⁺和Mg²⁺而言，三个强结合位点可能相同，并且这些位点位于靠近被强结合金属稳定的三级相互作用处。结合已发表的关于酵母苯丙氨酸tRNA的X射线数据，这些变宽数据使我们能够推测出强结合位点的一些合理位置。