Threonine synthase catalyzes the final step of threonine biosynthesis. The conversion of O-phosphohomoserine into threonine and inorganic phosphate is pyridoxal 5'-phosphate dependent. The Thr-synth_1 CD includes members from higher plants, cyanobacteria, archaebacteria and eubacterial groups. This CD, Thr-synth_2, includes enzymes from fungi and eubacterial groups, as well as, metazoan threonine synthase-like proteins.
Jiyao W et al.(2023). "The conserved domain database in 2023.",