1DXD:
reference: The role of cavities in protein dynamics: crystal structure of a photolytic intermediate of a mutant myoglobin., Brunori M, Vallone B, Cutruzzola F, Travaglini-Allocatelli C, Berendzen J, Chu K, Sweet RM, Schlichting I, Proc Natl Acad Sci U S A 2000 Feb 29;97(5):2058-63. PMID: 10681426

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