2V1W:
reference: Unusual binding interactions in PDZ domain crystal structures help explain binding mechanisms., Elkins JM, Gileadi C, Shrestha L, Phillips C, Wang J, Muniz JR, Doyle DA, Protein Sci. 2010 Apr;19(4):731-41. doi: 10.1002/pro.349. PMID: 20120020

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