2WNR:
reference: Structure of the Methanothermobacter thermautotrophicus exosome RNase PH ring., Ng CL, Waterman DG, Antson AA, Ortiz-Lombardia M, Acta Crystallogr D Biol Crystallogr. 2010 May;66(Pt 5):522-8. Epub 2010, Apr 21. PMID: 20445227

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