2HEM:
reference: NMR structure and Mg2+ binding of an RNA segment that underlies the L7/L12 stalk in the E.coli 50S ribosomal subunit., Zhao Q, Nagaswamy U, Lee H, Xia Y, Huang HC, Gao X, Fox GE, Nucleic Acids Res. 2005 Jun 6;33(10):3145-53. Print 2005. PMID: 15939932

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