2ZF9:
reference: Cohesin diversity revealed by the crystal structure of the anchoring cohesin from Ruminococcus flavefaciens., Alber O, Noach I, Rincon MT, Flint HJ, Shimon LJ, Lamed R, Frolow F, Bayer EA, Proteins. 2009 May 18;77(3):699-709. PMID: 19544570

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