3FN5:
reference: Crystal Structure of Streptococcus pyogenes Sortase A: IMPLICATIONS FOR SORTASE MECHANISM., Race PR, Bentley ML, Melvin JA, Crow A, Hughes RK, Smith WD, Sessions RB, Kehoe MA, McCafferty DG, Banfield MJ, J Biol Chem. 2009 Mar 13;284(11):6924-33. Epub 2009 Jan 6. PMID: 19129180

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