2.7.7.14 H146A site-directed mutagenesis, the mutant is almost inactive 721549 2.7.7.14 H226A mutation in histidine residue in the HxGH motif of the C-terminal CT domain. Decrease in activity 737597 2.7.7.14 H229A mutation in histidine residue in the HxGH motif of the N-terminal CT domain. Activity similar to wild-type activity 737597 2.7.7.14 H244A inactive C-domain mutant, presence of the mutant reduces splice variant Pcyt2alpha homodimerization and activity 738322 2.7.7.14 H244Y inactive C-domain mutant, presence of the mutant reduces splice variant Pcyt2alpha homodimerization and activity 738322 2.7.7.14 H35A inactive N-domain mutant, presence of the mutant reduces splice variant Pcyt2alpha homodimerization and activity 738322 2.7.7.14 H35A mutation in histidine residue in the HxGH motif of the N-terminal CT domain. Complete loss of activity 737597 2.7.7.14 H35Y inactive N-domain mutant, presence of the mutant reduces splice variant Pcyt2alpha homodimerization and activity 738322 2.7.7.14 H38A mutation in histidine residue in the HxGH motif of the N-terminal CT domain. Strong decrease in activity 737597 2.7.7.14 H422A site-directed mutagenesis, the mutant shows increased kcat and Vmax with ethanolamine phosphate compared to the wild-type enzyme 721549