3.6.1.12	Mg2+	required	209856, 755999	
3.6.1.12	MgCl2	maximum activity in presence of 100 mM MgCl2	722230	
3.6.1.12	MnCl2	up to 40% of the activity with MgCl2	722230	
3.6.1.12	additional information	divalent cation is absolutely required	722230