3SZP:
reference: The crystal structure of AphB, a virulence gene activator from Vibrio cholerae, reveals residues that influence its response to oxygen and pH., Taylor JL, De Silva RS, Kovacikova G, Lin W, Taylor RK, Skorupski K, Kull FJ, Mol Microbiol. 2011 Nov 7. doi: 10.1111/j.1365-2958.2011.07919.x. PMID: 22053934

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