The strength of the 3′-gauche effect dictates the structure of 3′-O-anthraniloyladenosine and its 5′-phosphate, two analogues of the 3′-end of aminoacyl-tRNA
作者:Parag Acharya、Barbara Nawrot、Mathias Sprinzl、Christophe Thibaudeau、Jyoti Chattopadhyaya
DOI:10.1039/a809350d
日期:——
N⇄pseudorotational equilibrium for 3′-O-anthraniloyladenosine 5′-phosphate and 5′-AMP. The 3′-O-anthraniloyladenosine and its 5′-phosphate are much more flexible than the isomeric 2′-counterparts as is evident from the temperature-dependent coupling constants analysis. The relative rate of the transacylation reaction of 2′(3′)-O-anthraniloyladenosine and its 5′-phosphate is cooperatively dictated by the two-state
带邻氨基苯甲酸的酵母tRNA Phe或大肠杆菌tRNA Val能够与EF-Tu * GTP形成稳定的复合物,因此认为2'-和3'- O-邻氨基苯乙腺苷及其对应的5'-磷酸盐是能够模仿氨酰基-tRNA的最小单位。由于3'- O-邻氨基苯甲酰腺苷与其2'-异构体相比还更有效地结合到EF-Tu * GTP络合物上,因此我们在此描述了指示3'- O-邻氨基苯甲酰腺苷及其5'的构象的立体电子特征。磷酸面对面的人它们的2'对应物,我们还讨论了它们的结构和热力学稳定性与腺苷和5'-AMP有何不同。已经发现的是,吸电子基团茴施加笨拙根据其是否是在2'-或在因为无论存在或不存在的O2'-N9的3'-位可变强度的效果笨拙效果,[GE (O2'-C2'-C1'-N9)],从而将组成糖部分的假旋转控制为North(N)型(C3'- endo)或South(S)型(C2'- endo)的构象。3'- Ô -anthraniloyladenosine