. Author manuscript; available in PMC: 2014 Aug 7.

Published in final edited form as: Protein Expr Purif. 2010 Nov 24;76(2):229–237. doi: 10.1016/j.pep.2010.11.008

Table 1.

Purification of His-tagged recombinant enzymes from Escherichia coli ^a,^b

Purification Steps	Enzyme	Total Protein /mg	Yield /%	Total Activity /U	Specific Activity /Umg⁻¹	Purification /fold
Crude Supernatant	RK	427 ± 20^c	100	15 400 ± 520	36.1 ± 1.4	1
	PRPPS	197 ± 13	100	2250 ± 154	11.4 ± 0.8	1
	APRT	454 ± 32	100	9620 ± 415	21.2 ± 1.2	1
	XGPRT	568 ± 53	100	3740 ± 176	6.6 ± 0.5	1
	UPRT	581 ± 60	100	15 600 ± 652	26.9 ± 2.1	1
	CTPS	427 ± 43	100	31 400 ± 1281	73.5 ± 5.7	1
Ni-NTA Column	RK	21.8 ± 2.2	5.1	1530 ± 62	70.2 ± 5.3	1.9
	PRPPS	1.0 ± 0.1	0.5	21.7 ± 0.9	21.7 ± 1.7	1.9
	APRT	22.8 ± 2.1	5.0	483 ± 32	21.2 ± 1.7	1.0
	XGPRT	24.4 ± 2.5	4.3	3120 ± 128	128 ± 10	20
	UPRT	14.8 ± 2.0	2.5	2120 ± 70	143 ± 14	5.3
	CTPS	20.2 ± 2.5	4.7	2280 ± 131	113 ± 11	1.5

The starting material was 40ml of crude E. coli supernatant.

One unit is defined as the conversion of 1 μmol of substrate/min at 25°C or 37C for UPRT and CTPS.

All results except enzyme activity are averages from 3 separate isolation procedures. The enzyme activity data are averages from 3 analyses for one of the isolations.

Uncertainties are expressed as standard deviation.