Purified NS2B/NS3 Serine Protease of Dengue Virus Type 2 Exhibits Cofactor NS2B Dependence for Cleavage of Substrates with Dibasic Amino Acids in Vitro*

  title={Purified NS2B/NS3 Serine Protease of Dengue Virus Type 2 Exhibits Cofactor NS2B Dependence for Cleavage of Substrates with Dibasic Amino Acids in Vitro*},
  author={Rohana Yusof and Stephen R Clum and Mary G. Wetzel and H. M. Krishna Murthy and Raji Padmanabhan},
  journal={The Journal of Biological Chemistry},
  pages={9963 - 9969}
Dengue virus type 2 NS3, a multifunctional protein, has a serine protease domain (NS3pro) that requires the conserved hydrophilic domain of NS2B for protease activity in cleavage of the polyprotein precursor at sites following two basic amino acids. In this study, we report the expression of the NS2B-NS3pro precursor inEscherichia coli as a fusion protein with a histidine tag at the N terminus. The precursor was purified from insoluble inclusion bodies by Ni2+ affinity and gel filtration… 

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