4EL8:
reference: Revealing nature's cellulase diversity: the digestion mechanism of Caldicellulosiruptor bescii CelA., Brunecky R, Alahuhta M, Xu Q, Donohoe BS, Crowley MF, Kataeva IA, Yang SJ, Resch MG, Adams MW, Lunin VV, Himmel ME, Bomble YJ, Science. 2013 Dec 20;342(6165):1513-6. doi: 10.1126/science.1244273. PMID: 24357319

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