4B1M:
reference: How nature can exploit nonspecific catalytic and carbohydrate binding modules to create enzymatic specificity., Cuskin F, Flint JE, Gloster TM, Morland C, Basle A, Henrissat B, Coutinho PM, Strazzulli A, Solovyova AS, Davies GJ, Gilbert HJ, Proc Natl Acad Sci U S A. 2012 Dec 3. PMID: 23213210

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