EXPRESSION OF HETEROLOGOUS PROTEINS IN BACTERIAL SYSTEM USING A GM-CSF FUSION TAG

摘要

Fusion tag comprising C terminus amino acids of human Granulocyte Macrophage Colony Simulating Factor (GM-CSF), START codon and enterokinase cleavage site and adapted to express other wise non expressible genes. A process for formation of the fusion tag comprising amplification of C terminus 45 amino acids from a full length human GM-CSF synthetic gene using gene specific forward primers which contains specific restriction site for providing START codon, and reverse primer containing sequences corresponding to enterokinase cleavage site, Fusion protein comprising fusion tag towards the N terminus, said fusion tag comprising C terminus amino acids of human Granulocyte Macrophage Colony Simulating Factor (GM-CSF), START codon and enterokinase cleavage site and adapted to express other wise non expressible genes, and non GM peptide towards the C-terminus. A method of producing the fusion protein, comprising transforming a host cell with the DNA expression vector as defined in and expressing said fusion protein. A method of purifying or isolating the fusion protein, using affinity chromatography to purify or isolate the fusion protein.An expression vector comprising a DNA sequence coding for a fusion protein said fusion protein comprising a fusion tag being capable of being used in N- terminus tagging, wherein the fusion tag has the 45 amino acid of human GM-CSF, START codon and enterokinase cleavage site.