2DSK:
reference: Structure of the catalytic domain of the hyperthermophilic chitinase from Pyrococcus furiosus., Nakamura T, Mine S, Hagihara Y, Ishikawa K, Uegaki K, Acta Crystallograph Sect F Struct Biol Cryst Commun. 2007 Jan 1;63(Pt, 1):7-11. Epub 2006 Dec 16. PMID: 17183162

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