In this paper,we report the results of a HF/6-31G** and B3LYP/6-31+G** computational investigation of the title reaction for the peptide bond synthesis catalyzed by a single adenine,guanine or uracil.Thus,the analysis of the geometry and energetics of the critical structures involved in this title reaction yields insight into the catalytic mode of action of RNA molecules.The imino form of adenine should not be considered as a prerequisite for A2451 to have function as a general acid-base catalyst.The other nucletides of RNA,guanine,cytosine,and uracil,have the similar general acid-base catalytic function and mechanism with those of adenine.
