4RD5:
reference: Crystal structure of the R-protein of the multisubunit ATP-dependent restriction endonuclease NgoAVII., Tamulaitiene G, Silanskas A, Grazulis S, Zaremba M, Siksnys V, Nucleic Acids Res. 2014 Dec 16;42(22):14022-30. doi: 10.1093/nar/gku1237. Epub, 2014 Nov 27. PMID: 25429979

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