Preparation of PTD4-Cu, Zn-SOD fusion protein

Objective To prepare PTD4-Cu, Zn-SOD fusion protein. Methods The recombinant plasmid of pET16b-Cu, Zn-SOD and pET16b-PTD4-Cu, Zn-SOD was transformed into Escherichia coli BL21 (DE3). Isopropyl β-D-1-thiogalactopyranoside was then added at a final concentration of 0.84 mmol/L, and the cells were incubated for 4 h to induce the expression of Cu, Zn-SOD and PTD4-Cu, Zn-SOD fusion protein.Lysozyme and ultrasound were used to lyse the bacteria, the supernatant was collected for 15% SDS-PAGE to analyze the expression of the target protein.Ni-NTA His bind resin was used to purify Cu, Zn-SOD protein and PTD4-Cu, Zn-SOD fusion protein under natural conditions.Western blot was used to identify the target protein. Results The results of Western blot showed that the purity of the target protein was about 90%, and the Cu, Zn-SOD protein with a molecular weight about 19 kDa and the PTD4-Cu, Zn-SOD fusion protein with a molecular weight about 20 kDa were found. Conclusion PTD4-Cu, Zn-SOD fusion protein is prepared successfully. Key words: tat Gene products, human immunodeficiency virus; Protein structure, tertiary; Superoxide dismutase; Proteins