PRODUCTION OF ACTIVE RECOMBINANT HUMAN CHYMASE FROM A CONSTRUCT CONTAINING THE ENTEROKINASE CLEAVAGE SITE OF TRYPSINOGEN IN-PLACE OF THE NATIVE PROPEPTIDE SEQUENCE

Human chymase, a chymotrypsin-like proteinase found in mast cells, was produced in an enzymatically active recombinant form. The protein was expressed in Escherichia coli as part of an insoluble fusion protein which was solubilized and renatured. The structure of the fusion prote in was NH2-ubiquitin-enterokinase cleavage site-chymase-COOH. The ente rokinase cleavage site of trypsinogen replaced the native propeptide s equence of chymase, allowing for activation by a readily available pro teinase (enterokinase) of known specificity. Characterization of refol ded-activated recombinant chymase with substrates and inhibitors demon strated properties identical to that of the native proteinase isolated from skin.