Crystallization and initial crystallographic analysis of phosphoglucosamine mutase from Bacillus anthracis

The enzyme phosphoglucosamine mutase from B. anthracis participates in the peptidoglycan-biosynthetic pathway. The expression, purification and crystallization of this enzyme are described; diffraction data have been collected to 2.7 Å resolution. The enzyme phosphoglucosamine mutase catalyzes the conversion of glucosamine 6-phosphate to glucosamine 1-phosphate, an early step in the formation of the nucleotide sugar UDP-N-acetylglucosamine, which is involved in peptidoglycan biosynthesis. These enzymes are part of the large α-d-phosphohexomutase enzyme superfamily, but no proteins from the phosphoglucosamine mutase subgroup have been structurally characterized to date. Here, the crystallization of phosphoglucosamine mutase from Bacillus anthracis in space group P3₂21 by hanging-drop vapor diffusion is reported. The crystals diffracted to 2.7 Å resolution under cryocooling conditions. Structure determination by molecular replacement was successful and refinement is under way. The crystal structure of B. anthracis phosphoglucosamine mutase should shed light on the substrate-specificity of these enzymes and will also serve as a template for inhibitor design