Production of Human Cu,Zn SOD with Higher Activity and Lower Toxicity in E. coli via Mutation of Free Cysteine Residues

Table 2

Atomic absorption measurements of Cu and Zn contents in SOD1 proteins.

SOD protein	Cu content		Zn content
	μg/mg	Cu/	μg/mg	Zn/
wtSOD1	4.346	1.37	2.787	0.85
mhSOD1/C111S	5.322	1.67	3.822	1.16

molecular weight of wtSOD1 and mhSOD1/C111S is calculated as 20 kDa.