5Z99:
reference: Molecular characterization of the interaction of sialic acid with the periplasmic binding protein from Haemophilus ducreyi., Setty TG, Mowers JC, Hobbs AG, Maiya SP, Syed S, Munson RS Jr, Apicella MA, Subramanian R, J Biol Chem. 2018 Oct 12. pii: RA118.005151. doi: 10.1074/jbc.RA118.005151. PMID: 30315109

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