2M1V:
reference: The Role of Magnesium(II) for DNA Cleavage Site Recognition in Group II Intron Ribozymes -- Solution Structure and Metal Ion Binding Sites of the RNA.DNA Complex., Skilandat M, Sigel RK, J Biol Chem. 2014 Jun 3. pii: jbc.M113.542381. PMID: 24895129

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