3VTR:
reference: Structural insights into cellulolytic and chitinolytic enzymes revealing crucial residues of insect beta-N-acetyl-D-hexosaminidase., Liu T, Zhou Y, Chen L, Chen W, Liu L, Shen X, Zhang W, Zhang J, Yang Q, PLoS One. 2012;7(12):e52225. doi: 10.1371/journal.pone.0052225. Epub 2012 Dec 27. PMID: 23300622

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