6WXP:
reference: Tight and specific lanthanide binding in a de novo TIM barrel with a large internal cavity designed by symmetric domain fusion., Caldwell SJ, Haydon IC, Piperidou N, Huang PS, Bick MJ, Sjostrom HS, Hilvert D, Baker D, Zeymer C, Proc Natl Acad Sci U S A. 2020 Nov 17. pii: 2008535117. doi:, 10.1073/pnas.2008535117. PMID: 33203677

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