3M7K:
reference: Unusual target site disruption by the rare-cutting HNH restriction endonuclease PacI., Shen BW, Heiter DF, Chan SH, Wang H, Xu SY, Morgan RD, Wilson GG, Stoddard BL, Structure. 2010 Jun 9;18(6):734-43. PMID: 20541511

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