Expression of human membrane type 1 matrix metalloproteinase in Pichia pastoris

A soluble, C-terminal truncated form of human membrane type 1 matrix metall oproteinase (MT1-MMP) containing the hemopexin-like domain was expressed in Pichia pastoris strain KM71. High levels of secreted protein were detected . Although the c-DNA for the proenzyme (Ala(21)-Glu(523) called Delta TM-MT 1-MMP) was cloned, almost only active MT1-MMP (Tyr(112)-GlU(523)) with iden tical N-terminus as described for the wildtype enzyme was isolated. This ac tive enzyme was highly purified and characterized with respect to its bioch emical properties, The recombinant protein showed high stability against au tolysis and proteolysis by yeast proteases, although the calculated in vivo half-life is rather low. The biochemical properties of this new MT1-MMP sp ecies were compared with the well-characterized catalytic domain (Ile(114)- Ile(318)) of MT1-MMP, The novel form of MT1-MMP exhibited a higher stabilit y against autolysis than the isolated catalytic domain (Ile(114)-Ile(318)). (C) 2000AcademicPress.