3NSM:
reference: Structural Determinants of an Insect {beta}-N-Acetyl-D-hexosaminidase Specialized as a Chitinolytic Enzyme., Liu T, Zhang H, Liu F, Wu Q, Shen X, Yang Q, J Biol Chem. 2011 Feb 11;286(6):4049-58. Epub 2010 Nov 24. PMID: 21106526

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