2.1.1.90	Ba2+	metal-free enzyme preparation has no activity, addition of Ba2+ restores 27% of the original activity	485660	
2.1.1.90	Ca2+	metal-free enzyme preparation has no activity, addition of Ca2+ restores 35% of the original activity	485660	
2.1.1.90	Co2+	metal-free enzyme preparation has no activity, addition of Co+ restores 46% of the original activity	485660	
2.1.1.90	Cobalt	the enzyme only binds the methyl group of methanol when the cobalt atom of its corrinoid prosthetic groups is present in the highly reduced Co(I) state. Formation of this redox state requires H2, hydrogenase, methyltransferase activation protein, and ATP	727819	
2.1.1.90	Iron	presence of 1.7 mol of non-heme iron per mol of enzyme	727819	
2.1.1.90	Mg2+	metal-free enzyme preparation has no activity, addition of Mg2+ restores 66% of the original activity	485660	
2.1.1.90	Mg2+	plays a role in binding of the corrinoid prosthetic group and in subunit association	727819	
2.1.1.90	Mn2+	metal-free enzyme preparation has no activity, addition of Mn2+ restores 27% of the original activity	485660	
2.1.1.90	Ni2+	metal-free enzyme preparation has no activity, addition of Ni2+ restores 21% of the original activity	485660	
2.1.1.90	Sr2+	metal-free enzyme preparation has no activity, addition of Sr2+ restores 20% of the original activity	485660	
2.1.1.90	Zinc	dependent on	726582	
2.1.1.90	Zn2+	0.1 mM used in assay conditions	757103	
2.1.1.90	Zn2+	beta subunit MtaB contains 1 mol Zn2+/mol subunit, Zn2+ can be substituted by Co2+	485665