3FPP:
reference: Crystal structure of the periplasmic component of a tripartite macrolide-specific efflux pump., Yum S, Xu Y, Piao S, Sim SH, Kim HM, Jo WS, Kim KJ, Kweon HS, Jeong MH, Jeon H, Lee K, Ha NC, J Mol Biol. 2009 Apr 17;387(5):1286-97. Epub 2009 Feb 28. PMID: 19254725

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