1RPO:
reference: Restored heptad pattern continuity does not alter the folding of a four-alpha-helix bundle., Vlassi M, Steif C, Weber P, Tsernoglou D, Wilson KS, Hinz HJ, Kokkinidis M, Nat Struct Biol 1994 Oct;1(10):706-16. PMID: 7634075

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