Crystal structure of Methanococcus jannaschii dihydroorotase with substrate bound.

ABSTRACT: Here, we report the X-ray structural analysis of dihydroorotase from Methanococcus jannaschii co-crystallized with dihydroorotate at pH 6.5. The crystals are isomorphous with the crystals of the apoenzyme, with space group P3₂21 and unit-cell dimensions a = b = 111.4, c = 101.2 Å. The structure was refined to R = 0.169 and R_free = 0.186 at a resolution of 1.87 Å at room temperature. During crystallization the degradative reaction took place, and the electron density in the active site corresponds to the substrate carbamoyl aspartate. Carbamoyl aspartate interacts with the protein in the active site in a manner similar to that observed for Escherichia coli and human dihydroorotases. However, the flexible loop (residues 140-151) adopts both conformations in the crystal,

SUBMITTER: Vitali J 

PROVIDER: S-EPMC12809426 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature