Expression of BMP2-Hydrophobin fusion protein in the tobacco plant and molecular dynamic evaluation of its simulated model

Plants are one of the ideal models for therapeutic protein production, however the recombinant protein purification problems in them must be overcome. Bone Morphogenetic Protein2 (BMP2) is employed for the restoration and construction of bone tissues. Hydrophobin is a fungal based protein with high hydrophobic characteristics. Due to this specificity, it is suitable for the purification of chimer protein from complex solutions when is fused to a protein utilizing an aqueous two-phase (A2P) technique. The plant optimized mature human BMP2 gene was designed and evaluated by in silico method. This process involves simulating molecular dynamics using the RMSD, RMSF and Gyration radius indexes. The synthesized Hyd-BMP2 gene was cloned into a pTRAkc-ERH plasmid and Transferred into Agrobacterium (Gv3101). The Nicotiana benthamiana plant leaves were co-agroinfiltrated with HA-Hyd-BMP2 and P19-pCambia1304 containing silencing suppressor. After purification of plant extract utilizing the A2P method, the sample was subjected to SDS-PAGE and Western-blot. By in silico study, the simulated fusion protein profitably shows reasonable protein compactness and the effect of amino acid substitution on protein–protein interaction is not remarkable. Western-blotting using anti HA tag has shown that the A2P technique partially purified the two 22 kDa and 44 kDa forms of Hydrophobin-BMP2. These results confirmed the presence of monomer and dimer forms of Hydrophobin-BMP2 proteins. Moreover, the expression level of the protein using P19 silencing suppressor increased six times and to 0.018% as shown by ELISA. This study presents a fast and easy technique for the purification of transient expressed pharmaceutical proteins from plants.