Biochemical Characterization of Exoribonuclease Encoded by SARS Coronavirus
2007
Chen, Ping (Wuhan University, Wuhan, P.R. China) | Jiang, Miao (Wuhan University, Wuhan, P.R. China) | Hu, Tao (Wuhan University, Wuhan, P.R. China) | Liu, Qingzhen (Wuhan University, Wuhan, P.R. China) | Chen, Xiaojiang S. (University of Southern California, Los Angeles, CA, USA) | Guo, Deyin (Wuhan University, Wuhan, P.R. China), E-mail: [email protected]
The nsp14 protein is an exoribonuclease that is encoded by severe acute respiratory syndrome coronavirus (SARS-CoV). We have cloned and expressed the nsp14 protein in Escherichia coli, and characterized the nature and the role(s) of the metal ions in the reaction chemistry. The purified recombinant nsp14 protein digested a 5'-labeled RNA molecule, but failed to digest the RNA substrate that is modified with fluorescein group at the 3'-hydroxyl group, suggesting a 3'-to-5' exoribonuclease activity. The exoribonuclease activity requires Mg²+ as a cofactor.
显示更多 [+] 显示较少 [-]