3K4Z:
reference: The unique binding mode of cellulosomal CBM4 from Clostridium thermocellum cellobiohydrolase A., Alahuhta M, Xu Q, Bomble YJ, Brunecky R, Adney WS, Ding SY, Himmel ME, Lunin VV, J Mol Biol. 2010 Sep 17;402(2):374-87. Epub 2010 Jul 21. PMID: 20654622

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