1IS8:
reference: Crystal structure of the stimulatory complex of GTP cyclohydrolase I and its feedback regulatory protein GFRP., Maita N, Okada K, Hatakeyama K, Hakoshima T, Proc Natl Acad Sci U S A 2002 Feb 5;99(3):1212-7. PMID: 11818540

This OCA Structure page
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