Cloning, expression, purification, crystallization and preliminary crystallographic studies of BceC, a UDP-glucose dehydrogenase from Burkholderia cepacia IST408.

Bacteria of the Burkholderia cepacia complex (Bcc) have emerged as important opportunistic pathogens, establishing lung infections in immunocompromised or cystic fibrosis patients. Bcc uses polysaccharide-biofilm production in order to evade the host immune response. The biofilm precursor UDP-glucuronic acid is produced by a twofold NAD(+)-dependent oxidation of UDP-glucose. In B. cepacia IST408 this enzymatic reaction is performed by the UDP-glucose dehydrogenase BceC, a 470-residue enzyme, the production and crystallization of which are described here. The crystals belonged to the orthorhombic space group P2(1)2(1)2(1) and contained four molecules in the asymmetric unit. Their crystallographic analysis at 2.09 A resolution and a molecular-replacement study are reported.