3B8N:
reference: Bacterial polysaccharide co-polymerases share a common framework for control of polymer length., Tocilj A, Munger C, Proteau A, Morona R, Purins L, Ajamian E, Wagner J, Papadopoulos M, Van Den Bosch L, Rubinstein JL, Fethiere J, Matte A, Cygler M, Nat Struct Mol Biol. 2008 Feb;15(2):130-8. Epub 2008 Jan 20. PMID: 18204465

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