6BND:
reference: Substrate Recognition by a Colistin Resistance Enzyme from Moraxella catarrhalis., Stogios PJ, Cox G, Zubyk HL, Evdokimova E, Wawrzak Z, Wright GD, Savchenko A, ACS Chem Biol. 2018 Apr 19. doi: 10.1021/acschembio.8b00116. PMID: 29631403

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