4Y1T:
reference: Structural Basis for Ca2+-mediated Interaction of the Perforin C2 Domain with Lipid Membranes., Yagi H, Conroy PJ, Leung EW, Law RH, Trapani JA, Voskoboinik I, Whisstock JC, Norton RS, J Biol Chem. 2015 Aug 25. pii: jbc.M115.668384. PMID: 26306037

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