1NOK:
reference: Ternary complex crystal structures of glycogen phosphorylase with the transition state analogue nojirimycin tetrazole and phosphate in the T and R states., Mitchell EP, Withers SG, Ermert P, Vasella AT, Garman EF, Oikonomakos NG, Johnson LN, Biochemistry 1996 Jun 11;35(23):7341-55. PMID: 8652510

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