2QDB:
reference: Electrostatic effects in a network of polar and ionizable groups in staphylococcal nuclease., Baran KL, Chimenti MS, Schlessman JL, Fitch CA, Herbst KJ, Garcia-Moreno BE, J Mol Biol. 2008 Jun 20;379(5):1045-62. Epub 2008 Apr 16. PMID: 18499123

This OCA Structure page
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