Table 1.

Purification of PDE from Sphingobium sp. TCM1^a.

Step	Total activityb (µmol · min−1)	Total protein (mg)	Specific activity (µmol · min−1 · mg−1)	Purification (fold)	Yield (%)
Crude extract	463	2312	0.20	1.00	100
Ammonium sulfate fractionation	366	491	0.74	3.72	79.0
Phenyl Sepharose HP	251	202	1.24	6.19	54.2
Q Sepharose HP	94.9	5.35	17.7	88.6	20.5
Superdex 200 pg	68.4	2.33	29.4	147	14.8

^aStarting material was 47.4 g of wet cells.

^bThe activity of Sb-PDE was measured using the standard assay mixture with BpNpp as the substrate.