2KSF:
reference: Membrane domain structures of three classes of histidine kinase receptors by cell-free expression and rapid NMR analysis., Maslennikov I, Klammt C, Hwang E, Kefala G, Okamura M, Esquivies L, Mors K, Glaubitz C, Kwiatkowski W, Jeon YH, Choe S, Proc Natl Acad Sci U S A. 2010 Jun 15;107(24):10902-7. Epub 2010 May 24. PMID: 20498088

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