4HDM:
reference: Structural Insights into the Function of the Nicotinate Mononucleotide:phenol/p-cresol Phosphoribosyltransferase (ArsAB) Enzyme from Sporomusa ovata., Newmister SA, Chan CH, Escalante-Semerena JC, Rayment I, Biochemistry. 2012 Oct 15. PMID: 23039029

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