Structure determination of histidine decarboxylase from Lactobacillus 30a at 3.0 Å resolution

The crystal structure of histidine decarboxylase from Lactobacillus 30a has been determined by X-ray diffraction methods to a resolution of 3.0 Å. This protein is a pyruvoyl-dependent enzyme that is formed by an unusual self-activation process. The structure was determined from an electron density map calculated using multiple isomorphous replacement phases from two heavy-atom derivatives and included contributions from anomalous scattering measurements. The final mean figure of merit was 0.79, based on 28,805 independent reflections.