3UDC:
reference: Structure and molecular mechanism of an anion-selective mechanosensitive channel of small conductance., Zhang X, Wang J, Feng Y, Ge J, Li W, Sun W, Iscla I, Yu J, Blount P, Li Y, Yang M, Proc Natl Acad Sci U S A. 2012 Oct 16. PMID: 23074248

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