SYNTHESIS AND CLEAVAGE-SECRETION OF ENZYMATICALLY ACTIVE-RABBIT ANGIOTENSIN-CONVERTING ENZYME IN PICHIA-PASTORIS

Many biologically important ectoproteins that are anchored in the plas ma membrane via a hydrophobic domain undergo a proteolytic cleavage pr ocess, which releases the ectodomain to the extracellular milieu in a regulated fashion. Ansotensin-converting enzyme (ACE) is one such prot ein that is secreted from human and mouse cells by its cleavage at one of two alternative sites in the ectodomain. Here, we report similar c leavage-secretion of ACE in the yeast Pichia pastoris. The cleavage si te used in yeasts was identical to one of the two sites used in mouse cells. Moreover, as in mammalian cells, ACE secretion in yeast was inh ibited by compound 3, a potent inhibitor of the metzincin family of me talloproteases. ACE proteins cleavage-secreted from yeast and from mam malian cells had identical enzymatic properties. These results demonst rate the existence of a secretase activity in yeast whose properties c losely resemble those of the mammalian ACE secretase.