4Y1N:
reference: Crystal structure of group II intron domain 1 reveals a template for RNA assembly., Zhao C, Rajashankar KR, Marcia M, Pyle AM, Nat Chem Biol. 2015 Dec;11(12):967-72. doi: 10.1038/nchembio.1949. Epub 2015 Oct , 26. PMID: 26502156

This OCA Structure page
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