1XWQ:
reference: Study of the active site residues of a glycoside hydrolase family 8 xylanase., Collins T, De Vos D, Hoyoux A, Savvides SN, Gerday C, Van Beeumen J, Feller G, J Mol Biol 2005 Nov 25;354(2):425-35. Epub 2005 Oct 10. PMID: 16246370

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