Construction and expression of a synthetic gene encoding nonstructural glycoprotein NS1 of dengue 2 virus in Pichia pastoris

Objectives To express and characterize NS1 of Indonesian-specific DENV2 virus in Pichia pastoris (P. pastoris). Methods A codon optimized synthetic gene derived from the DENV-2 NS1 amino acid sequences was synthesized commercially and inserted into the P. pastoris pPICZαA expression vector. The recombinant DENV-2 NS1 protein was purified by Ni-NTA affinity chromatography, and its antigenicity was tested. Results The recombinant DENV-2 NS1 protein was secreted as a protein with a molecular weight of ∼45 kDa, and the optimal expression condition was achieved by induction with 2% (v/v) methanol for 72 h. The purified recombinant DENV-2 NS1 protein was able to interact with a monoclonal antibody of NS1 in a commercial rapid test. Conclusions The resulting recombinant DENV-2 NS1 protein produced in P. pastoris KM71 is a potential candidate for use in the development of a dengue diagnostic kit and vaccine.