1U3M:
reference: Prion protein NMR structures of chickens, turtles, and frogs., Calzolai L, Lysek DA, Perez DR, Guntert P, Wuthrich K, Proc Natl Acad Sci U S A 2005 Jan 18;102(3):651-5. Epub 2005 Jan 12. PMID: 15647366

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