1JN1:
reference: Structure of 2C-methyl-D-erythrol-2,4-cyclodiphosphate synthase from Haemophilus influenzae: activation by conformational transition., Lehmann C, Lim K, Toedt J, Krajewski W, Howard A, Eisenstein E, Herzberg O, Proteins 2002 Oct 1;49(1):135-8. PMID: 12211023

This OCA Structure page
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