6D7R:
reference: Crystal structure of an inactive variant of the quorum-sensing master regulator HapR from the protease-deficient non-O1, non-O139 Vibrio cholerae strain V2., Cruite J, Succo P, Raychaudhuri S, Kull FJ, Acta Crystallogr F Struct Biol Commun. 2018 Jun 1;74(Pt 6):331-336. doi:, 10.1107/S2053230X18006519. Epub 2018 May 17. PMID: 29870016

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