research communications
The thymidylate synthases ThyA and Thy1 are enzymes that catalyse the formation of thymidine monophosphate from 2′-deoxyuridine monophosphate. Thy1 (or ThyX) requires flavin for catalytic reactions, while ThyA does not. In the present study, the crystal structure of the flavin-dependent thymidylate synthase Thy1 from Thermus thermophilus HB8 (TtThy1, TTHA1096) was determined in complex with FAD and phosphate at 2.5 Å resolution. TtThy1 is a tetrameric molecule like other Thy1 proteins, to which four FAD molecules are bound. In the crystal of TtThy1, two phosphate ions were bound to each dUMP-binding site. The characteristic feature of TtThy1 is the existence of an extra C-terminal domain (CTD) consisting of three α-helices and a β-strand. The function of the CTD is unknown and database analysis showed that this CTD is only shared by part of the Deinococcus–Thermus phylum.
Keywords: flavin-dependent thymidylate synthase; pyrimidine nucleotide biosynthetic pathway; C-terminal domain.
Supporting information
Portable Document Format (PDF) file https://doi.org/10.1107/S2053230X19007192/tb5143sup1.pdf |
PDB reference: thymidylate synthase, 6j61