Purification, crystallization and X-ray crystallographic analysis of galactose-1-phosphate uridylyltransferase from Debaryomyces hansenii

초록

Galactose-1-phosphate uridylyltransferase (GALT) is the second enzyme in the Leloir pathway that reversibly converts galactose-1-phosphate to glucose-1-phosphate. GALT deficiency can cause growth defects in both prokaryotes and eukaryotes. Likewise, in humans, damage of this enzyme leads to a toxic syndrome known as galactosemia type I. In this study, to understand structural features and the underlying molecular mechanism of GALT in yeast, the crystal of GALT from Debaryomyces hansenii was determined at a resolution of 2.8 Å. The crystal of D. hansenii (DhGALT) belonged to the space group C2221, with the unit cell parameters a = 88.5 Å, b = 122.3 Å, c = 154.2 Å, α = β = γ = 90°. Two macromolecules were present in the asymmetric unit of the crystal. Following its structural determination, further study will be done for elucidating the structural features and reaction mechanism in fungal species.