Production of a 135-residue long N-truncated human keratinocyte growth factor 1 in Escherichia coli

Table 2 Purification of the KGF-1₁₃₅ from the fusion protein expressed in E. coli

Purification step	Concentration (mg/mL)	Volume (mL)	Total protein (mg)	Fusion protein (tag-free protein) (mg)	Purity (%)^a	Yield (%)^b
Crude extract	2.7 ± 2.1	70.0	190.3 ± 3.2	12.3 ± 4.0 (10.5 ± 0.3)	6.4	100
HisTrap, 5 mL	0.3 ± 0.0	60.0	19.2 ± 0.1	13.1 ± 0.2 (9.7 ± 0.3)	68.2	92.5
HiTrap SP, 5 mL	0.3 ± 0.0	20.0	5.6 ± 0.1	NA (5.6 ± 0.1)	100	53.0

^aPurity was analyzed by densitometry using ImageJ and C18 RP HPLC.
^bYield was calculated by dividing the tag-free protein of each purification product by the tag-free protein in the crude extract

ISSN: 1475-2859