Crystal structure of Lactobacillus species 30a Ornithine Decarboxylase has been determined to 3.0 Å resolution by Cory Momany, Stephen Ernst, Ratna Ghosh, Ning-Leh Chang, and Marvin L. Hackert
J. Mol. Biol. (1995) 252, 643-655.
PDB code 1ORD.

Shown here is a dimer of two identical subunits (730 residues per subunit). Active enzyme is a dodecamer (ca. 106 Da) composed of six dimers with overall D6 symmetry (622 in crystallographic notation).
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