4.1.3.22 Co2+ Mn2+, Mg2+ or Co2+ required 33254 4.1.3.22 Mg2+ Km for MgCl2: 0.1 mM 33254 4.1.3.22 Mg2+ or an equivalent divalent cation is required 33253, 33254 4.1.3.22 Mn2+ Mn2+, Mg2+ or Co2+ required 33254