Crystallization and preliminary X-ray crystallographic analysis of the α-2,6-sialyltransferase PM0188 from Pasteurella multosida

Sialyltransferase is an enzyme that transfers the sialic acid moiety from cytidine-5-monophospho-N-acetylneuraminic acid (CMP-NeuAc) to the carbohydrate group of various glycoproteins. These glycoproteins are involved in inflammation, embryogenesis, immune defence and metastasis of cancer cells by cell–cell interactions or cell–matrix interactions. The α-2,6-sialyltransferase PM0188 from Pasteurella multocida was purified using affinity-column chromatographic methods and crystallized using the hanging-drop vapour-diffusion method at 293 K. MAD data were collected to 1.9 Å resolution from an SeMet-substituted crystal. The crystal belongs to space group P2₁, with unit-cell parameters a = 52.9, b = 61.0, c = 64.6 Å, α = γ = 90, β = 112.3°. Assuming the presence of one molecule in the asymmetric unit, the solvent content is estimated to be about 45%.