Improving the mda-7/IL-24 refolding and purification process using optimized culture conditions based on the structure characteristics of inclusion bodies

Bioresources and Bioprocessing

Table 5 The simplified purification process of the washing steps

Washing step	Total protein (mg)	mda-7/IL-24 (mg)	mda-7/IL-24 yield (%)	mda-7/IL-24 purity (%)
Before washing	105	68	-	65
Buffer I	84	61	89	73
Buffer II	65	56	92	86
Buffer III	53	49	88	92
Deionized water	50	48	98	96

The wet weight of the E. coli cells was 3.75 g from 1 L culture medium, and 105 mg IBs was obtained after disruption. mda-7/IL-24 comprised up to 30% of the total protein. The total target protein lost 29% during the washes and 8.4% during the dialysis. The final purity of mda-7/IL-24 was about 95%.