1OSB:
reference: Recognition and processing of the origin of transfer DNA by conjugative relaxase TrwC., Guasch A, Lucas M, Moncalian G, Cabezas M, Perez-Luque R, Gomis-Ruth FX, de la Cruz F, Coll M, Nat Struct Biol 2003 Dec;10(12):1002-10. PMID: 14625590

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