2HAU:
reference: The crystal structure of iron-free human serum transferrin provides insight into inter-lobe communication and receptor binding., Wally J, Halbrooks PJ, Vonrhein C, Rould MA, Everse SJ, Mason AB, Buchanan SK, J Biol Chem. 2006 Aug 25;281(34):24934-44. Epub 2006 Jun 22. PMID: 16793765

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