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bioRxiv · 10.64898/2026.04.02.716094

Structural analysis of Helicobacter pylori glutamate racemase in a monoclinic crystal form

Spiliopoulou, M.·Schulz, E. C.
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Abstract

Glutamate racemase (MurI) catalyzes the stereochemical interconversion of L-glutamate to D-glutamate, a key element of bacterial peptidoglycan biosynthesis. In this study, we present the crystal structure of Helicobacter pylori glutamate racemase at 1.43 [A] and in monoclinic symmetry, as previously reported models, but different unit-cell parameters. The present model contains a single dimer and retains the previously described head-to-head dimer arrangement. The differences between the models arise from variations in unit-cell parameters, which lead to altered crystal packing interactions rather than changes in the quaternary assembly. The monomeric fold and active-site architecture remain conserved and are consistent with the catalytic features described for bacterial glutamate racemases. This structure provides an updated, high-resolution structural model for H. pylori glutamate racemase and highlights the variability in crystal packing within the same space group.

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Spiliopoulou, M., Schulz, E. C.. 2026-04-03. Structural analysis of Helicobacter pylori glutamate racemase in a monoclinic crystal form. https://doi.org/10.64898/2026.04.02.716094

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