ABSTRACT
A number of recombinant plasmids for expression of artificial genes encoding human granulocyte-macrophage colony stimulating factor (GM-CSF) were constructed. A hybrid gene was obtained that contains a sequence encoding the leader peptide and a tandem of two IgG-binding domains of protein A from Staphylococcus aureus coupled, through an enteropepdidase linker, to a synthetic gmcsf gene. The construction enables Escherichia coli to carry out biosynthesis of the hybrid protein and its subsequent transport into the periplasmic space of bacteria. Another hybrid gene, combining sequences for the signal peptide of the E.coli outer membrane protein OmpA and GM-CSF, was obtained using polymerase chain reaction. The localization of the mature protein produced by the hybrid gene was found to depend on the strength of the promoter used.
