5ZRF:
reference: Structural insights into the gating of DNA passage by the topoisomerase II DNA-gate., Chen SF, Huang NL, Lin JH, Wu CC, Wang YR, Yu YJ, Gilson MK, Chan NL, Nat Commun. 2018 Aug 6;9(1):3085. doi: 10.1038/s41467-018-05406-y. PMID: 30082834

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