Tsunoda M, Takenaka A, Cavarelli J, Rees B, Thierry J C, Moras D
Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan.
Nucleic Acids Symp Ser. 1995(34):65-6.
Based upon the X-ray structures of complexes between tRNAAsp and aspRS including ATP or Asp-AMP, several electrostatic potentials were calculated by solving the Poisson-Boltzmann equation. The potentials indicate clearly that a Mg2+ ion is essential for binding of ATP and that aspartate is identified electrostatically. The alpha-carboxyl group is forced to contact with the alpha-phosphorus atom of ATP, suggesting its inversion to form an Asp-AMP. When the cognate tRNA is bound to the aspRS:Asp-AMP complex, the 3'-hydroxyl group is located in an electrostatically favorable position to transfer the amino acid as a class II aminoacylation.
基于天冬氨酸转运核糖核酸（tRNAAsp）与天冬氨酸-tRNA合成酶（aspRS）形成的包含三磷酸腺苷（ATP）或天冬氨酰-单磷酸腺苷（Asp-AMP）的复合物的X射线结构，通过求解泊松-玻尔兹曼方程计算了几种静电势。这些电势清楚地表明，镁离子（Mg2+）对于ATP的结合至关重要，并且天冬氨酸是通过静电作用识别的。α-羧基被迫与ATP的α-磷原子接触，这表明它会发生反转以形成Asp-AMP。当同源tRNA与aspRS：Asp-AMP复合物结合时，3'-羟基位于静电有利位置，以便作为II类氨基酰化作用转移氨基酸。
