1. School of Life Sciences, Jilin University, Changchun, Jilin 130012, People’s Republic of China
2. Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun, Jilin 130012, People’s Republic of China
3. National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun, Jilin 130012, People’s Republic of China