Co2+
activates, can substitute for Mg2+
Co2+
can partially replace Mg2+ in activation
Co2+
Co2+ is able to substitute nfor Mg2+
Mg2+
divalent cation required, Mg2+ most effective
Mg2+
Mn2+, Co2+, Ca2+ are able to substitute for Mg2+ (94%-44% relative activity)
Mn2+
activates, can substitute for Mg2+
Mn2+
can partially replace Mg2+ in activation
Mn2+
Mn2+ is able to substitute nfor Mg2+
more
slight activation by trivalent cations, no effect by monovalent cations