4.2.1.138	Mg2+	more than 5 mM MgCl2 is required for maximum activity. The enzyme reaction is unable to proceed without MgCl2	715629	
4.2.1.138	Mn2+	38% activity (relative to the activity in the presence ofMg2+) is retained in the presence of 5 mM Mn2+	715629	
4.2.1.138	additional information	no activity is observed for Fe2+, Co2+, Zn2+, Ni2+, or Cu2+	715629