2YK6:
reference: Structure and Mechanism of the Lipooligosaccharide Sialyltransferase from Neisseria meningitidis., Lin LY, Rakic B, Chiu CP, Lameignere E, Wakarchuk WW, Withers SG, Strynadka NC, J Biol Chem. 2011 Oct 28;286(43):37237-48. Epub 2011 Aug 31. PMID: 21880735

This OCA Structure page
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