An UDP-N-acetylglucosamine 2-epimerase belongs to the family of isomerase, specifically those racemases and epimarases which act on carbohydrates and participate in amino sugars metabolism. Amino sugars are parts of aminoglycosides, a class of antimicrobial compounds that inhibit bacterial protein synthesis. The Enzyme catalyzes the reversible epimerization at C-2 of UDP-N-acetylglucosamine (UDP-GlcNAc) to produce UDP-N-acetylmannosamine (UDP-ManNAc). The presented crystal structure is an apo-form of the protein. The homodimeric epimerase is composed of two similar alpha/beta/alpha sandwich domains with the active site located in the deep cleft at the domain interface. Comparison with other known structures (apo- and complexes with substrate) has revealed big interdomain movement that is implicated in the regulatory mechanism.