2A02:
reference: Signal transduction pathway of TonB-dependent transporters., Ferguson AD, Amezcua CA, Halabi NM, Chelliah Y, Rosen MK, Ranganathan R, Deisenhofer J, Proc Natl Acad Sci U S A. 2007 Jan 9;104(2):513-8. Epub 2006 Dec 29. PMID: 17197416

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