1GZ0:
reference: The structure of the RlmB 23S rRNA methyltransferase reveals a new methyltransferase fold with a unique knot., Michel G, Sauve V, Larocque R, Li Y, Matte A, Cygler M, Structure (Camb) 2002 Oct;10(10):1303-15. PMID: 12377117

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