A method for the recombinant production and purification of a protein
kinase selected from the group consisting of tyrosine protein kinases and
serine/threonine kinases by expressing a nucleic acid encoding said
kinase in a microbial host cell, forming inclusion bodies containing said
kinase, isolating, solubilizing, naturing, and purifying said kinase
wherein said purification is performed by hydrophobic interaction with an
hydrophobic adsorbent under conditions whereby at least 70% of said
protein kinase are not bound to said adsorbent and the protein kinase not
bound to said adsorbent is recovered.