3BD1:
reference: Transitive homology-guided structural studies lead to discovery of Cro proteins with 40% sequence identity but different folds., Roessler CG, Hall BM, Anderson WJ, Ingram WM, Roberts SA, Montfort WR, Cordes MH, Proc Natl Acad Sci U S A. 2008 Feb 19;105(7):2343-8. Epub 2008 Jan 28. PMID: 18227506

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