2TCI:
reference: X-ray crystallographic studies on hexameric insulins in the presence of helix-stabilizing agents, thiocyanate, methylparaben, and phenol., Whittingham JL, Chaudhuri S, Dodson EJ, Moody PC, Dodson GG, Biochemistry 1995 Nov 28;34(47):15553-63. PMID: 7492558

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