2QV6:
reference: A New Use for a Familiar Fold: The X-ray Crystal Structure of GTP-Bound GTP Cyclohydrolase III from Methanocaldococcus jannaschii Reveals a Two Metal Ion Catalytic Mechanism(,)., Morrison SD, Roberts SA, Zegeer AM, Montfort WR, Bandarian V, Biochemistry. 2008 Jan 8;47(1):230-42. Epub 2007 Dec 4. PMID: 18052207

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