3VNV:
reference: Mechanism for template-independent terminal adenylation activity of Qbeta replicase., Takeshita D, Yamashita S, Tomita K, Structure. 2012 Oct 10;20(10):1661-9. doi: 10.1016/j.str.2012.07.004. Epub 2012, Aug 9. PMID: 22884418

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