2.4.1.90	Ca2+	10 mM used in assay conditions	757639	
2.4.1.90	Ca2+	about 50% of the activity with Mn2+	489555	
2.4.1.90	Ca2+	active only with mutant enzymes M334H and M344E, no activity with wild-type enzyme and mutants M344A, M344S, and M344Q	658032	
2.4.1.90	Ca2+	can partially replace Mn2+	489493	
2.4.1.90	Ca2+	slight activation	660309	
2.4.1.90	Co2+	activates, not as effective as Mn2+	660309	
2.4.1.90	Co2+	activation at 14.9% of the activity with Mn2+	489526	
2.4.1.90	Co2+	less active than Mn2+ with wild-type and mutant enzymes	658032	
2.4.1.90	Fe2+	no activation	489555	
2.4.1.90	Fe2+	partial activation	489555