4.2.1.31	Co2+	can replace Fe2+	
4.2.1.31	Fe2+	activates at 0.01-0.1 mM in the presence of Na2S and thiol, dependent on sequence of addition of compounds	
4.2.1.31	Fe2+	353% activation at 2 mM	
4.2.1.31	Mn2+	49% activation at 2 mM	
4.2.1.31	additional information	-	
4.2.1.31	Ni2+	can replace Fe2+