2O1H:
reference: Structural effects of naturally occurring human blood group B galactosyltransferase mutations adjacent to the DXD motif., Persson M, Letts JA, Hosseini-Maaf B, Borisova SN, Palcic MM, Evans SV, Olsson ML, J Biol Chem. 2007 Mar 30;282(13):9564-70. Epub 2007 Jan 26. PMID: 17259183

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