| abstract |
Amplified expression of recombinant DNA products is achieved in hosts expressing proteases that cleave at multi-basic amino acid residues. To this end, cDNAs encoding granulocyte-macrophage colony stimulating factor (GM-CSF) are mutated such that one or both of the arginine residues at positions 23 and 24 of the protein product are deleted or replaced by non-basic amino acid residues. The GM-CSF analogs thus obtained maintain the activity of the wild-type protein. |