3SXE:
reference: Sequence-dependent effects of cryoprotectants on the active sites of the human ABO(H) blood group A and B glycosyltransferases., Johal AR, Schuman B, Alfaro JA, Borisova S, Seto NO, Evans SV, Acta Crystallogr D Biol Crystallogr. 2012 Mar;68(Pt 3):268-76. Epub 2012 Feb 14. PMID: 22349229

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