4IDW:
reference: High-resolution powder X-ray data reveal the T6 hexameric form of bovine insulin., Margiolaki I, Giannopoulou AE, Wright JP, Knight L, Norrman M, Schluckebier G, Fitch AN, Von Dreele RB, Acta Crystallogr D Biol Crystallogr. 2013 Jun;69(Pt 6):978-90. doi:, 10.1107/S0907444913003867. Epub 2013 May 11. PMID: 23695242

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