2HIN:
reference: N15 Cro and lambda Cro: orthologous DNA-binding domains with completely different but equally effective homodimer interfaces., Dubrava MS, Ingram WM, Roberts SA, Weichsel A, Montfort WR, Cordes MH, Protein Sci. 2008 May;17(5):803-12. Epub 2008 Mar 27. PMID: 18369196

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