Theoretical study on the binding mechanism between N6-methyladenine and natural DNA bases Qi-Xia Song, Zhen-Dong Ding, Jian-Hua Liu, Yan Li, Hai-Jun Wang The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu, 214122, China _________________________ Corresponding author: Hai-Jun Wang (e-mail: wanghj@jiangnan.edu.cn; 86-0510-85917763) Tel: 13382888162; Fax: 38 Supplementary information Fig. S1. The optimized geometries for the bases calculated at the MP2/6-31G** level: adenine (A), guanine (G), thymine (T), and cytosine (C). Fig. S2. The optimized configurations for base pairs including m6A (trans and cis forms) calculated at the MP2/6-31G** level in aqueous solution. H-bonds are indicated by dotted line, and the corresponding atom numbering is given. Fig. S3. AIM analysis (MP2/6-31G**, in aqueous solution) of the base pairs with bond critical points, and the corresponding bond critical points are given. 39 A G 40 T C Fig. S1. The optimized geometries for the bases calculated at the MP2/6-31G** level: adenine (A), guanine (G), thymine (T), and cytosine (C). 41 cis-m6A:A cis-m6A:T 42 cis-m6A:C cis-m6A:G 43 trans-m6A:A trans-m6A:T 44 trans-m6A:C trans-m6A:G Fig. S2. The optimized configurations for base pairs including m6A (trans and cis forms) calculated at the MP2/6-31G** level in aqueous solution. H-bonds are indicated by dotted line, and the corresponding atom numbering is given. 45 cis-m6A:A cis-m6A:T 46 cis-m6A:C cis-m6A:G 47 trans-m6A:A trans-m6A:T 48 trans-m6A:C trans-m6A:G Fig. S3. AIM analysis (MP2/6-31G**, in aqueous solution) of the base pairs with bond critical points, and the corresponding bond critical points are given. 49