Purification of recombinant human phosphodiesterase 7A expressed in Dictyostelium discoideum.

Authors: Arya R, Gupta S, Aslam S, Kaur NJ, Seth A, Eapen MS, Malik R, Vijayakrishnan L, Saini KS.
Publisher/Year: Protein Expr Purif. 2008 Oct;61(2):149-54. Epub 2008 May 14.
Pub Med ID/Journal ID: PMID:18547817


Phosphodiesterase plays an important role in regulating inflammatory pathways and T cell function. The development of phosphodiesterase 7 inhibitor may give better efficacy profile over phosphodiesterase 4 inhibitors. However, the recombinant phosphodiesterase 7 is required in large quantity for high-throughput screening of new drugs by in vitro enzymatic assays. In the present study, recombinant human PDE7A1 was expressed in Dictyostelium discoideum under the control of constitutively active actin-15 promoter. The cytosolic localization of the expressed protein was confirmed by immunofluorescence studies. Upto 2 mg of recombinant protein was purified using His-Tag affinity column chromatography followed by ion-exchange Resource Q column purification. The recombinant protein expressed in D. discoideum followed Michaelis-Menten kinetics similar to the protein expressed in mammalian system and showed no major changes in affinity to substrate or inhibitors. Thus, our study clearly demonstrates a robust expression system for successful bulk production of pharmacologically active isoform of human PDE7A1 required for high-throughput assays.