Fig. 5.

Inhibition of MtFBPaseII by Li⁺. Activity of Wt and T84S mutant were assessed for lithium sensitivity. IC₅₀ curves for Wt-MtFBPaseII and T84S-MtFBPaseII, both at 30 nM enzyme concentration, show that the serine mutant and wildtype protein have similar sensitivity to lithium. Lithium concentration was tested from 0 to 3333 μM. Since threonine is part of a conserved lithium sensitive motif, the effect of mutagenesis of this residue on activity is important.