Self-association studies of the bifunctional N-acetylglucosamine-1-phosphate uridyltransferase from Escherichia coli.

ABSTRACT: The N-acetylglucosamine-1-phosphate uridyltransferase (GlmU) is a key bifunctional enzyme in the biosynthesis of UDP-GlcNAc, a precursor in the synthesis of cell wall peptidoglycan. Crystal structures of the enzyme from different bacterial strains showed that the polypeptide forms a trimer through a unique parallel left-handed beta helix domain. Here, we show that the GlmU enzyme from Escherichia coli forms a hexamer in solution. Sedimentation equilibrium analytical ultracentrifugation demonstrated that the enzyme is in a trimer/hexamer equilibrium. Small-angle X-ray scattering studies were performed to determine the structure of the hexameric assembly and showed that two trimers assemble through their N-terminal domains. The interaction is mediated by a loop that undergoes a large conform

SUBMITTER: Trempe JF 

PROVIDER: S-EPMC3081552 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature