Expression, purification and characterisation of a functional phosphatidylinositol-specific phospholipase C-delta 1 protein in Escherichia coli.

Inositol-lipid-specific phospholipase C-delta 1 (PtdIns-PLC delta 1) was expressed in Escherichia coli as a fusion protein containing a short 22-amino-acid lac-Z-derived amino terminus. Under appropriate conditions, the phospholipase constituted approximately 0.2% of the detergent-soluble protein and could be purified to near homogeneity in a simple three step protocol. The catalytic properties of the purified enzyme closely resemble those of the eukaryote-derived protein. The suitability of bacterial expression for the investigation of PtdIns-PLC delta regulation is discussed.