Correction to: Nature https://doi.org/10.1038/s41586-018-0238-4Published online 20 June 2018

In this Letter, the isotopologue used to demonstrate hydrogen atom abstraction from CTP was incorrectly identified as 2′,3′,4′,5′,5-deutero-CTP, whereas the isotopologue we used was 3′,4′,5′,5-deutero-CTP. (Boldface indicates where changes were made.) In the main text, the sentence “Incubation of rVIP with SAM and CTP deuterated at the 2′, 3′, 4′, 5′ and 5 positions (deuCTP), increased the −m/z of 5ʹ-dA from 250.1 to 251.1, consistent with the transfer of one deuterium from deuCTP to 5ʹ-dA.” should have read “Incubation of rVIP with SAM and CTP deuterated at the 3′, 4′, 5′ and 5 positions (deuCTP) increased the −m/z of 5ʹ-dA from 250.1 to 251.1, consistent with the transfer of one deuterium from deuCTP to 5ʹ-dA.”. In the Extended Data Fig. 3 legend the sentence “When rVIP was incubated with SAM and CTP deuterated at the 2′, 3′, 4′, 5′ and 5 positions (deuCTP), the −m/z of 5′-dA increased from 250.1 to 251.1, consistent with the transfer of one deuterium from deuCTP to 5′-dA•.” should have read: “When rVIP was incubated with SAM and CTP deuterated at the 3′, 4′, 5′ and 5 positions (deuCTP), the −m/z of 5′-dA increased from 250.1 to 251.1, consistent with the transfer of one deuterium from deuCTP to 5′-dA•.”

Similarly, the name of the isotopologue appeared incorrectly in the Supplementary Information. In the Supplementary Information section ‘Hydrogen atom abstraction specificity’ the sentence “Reactions of 100 μL total volume contained 100 μM rVIP, 50 mM HEPES pH 7.5, 150 mM KCl, 1 mM SAM, and 1 mM deuterium-labeled CTP (site-specifically labeled CTP contains deuterium at the following position; (2'-2H, 3'-2H, 4'-2H, or 5'-2H2-CTP)).” should have read: "Reactions of 100 μL total volume contained 100 μM rVIP, 50 mM HEPES pH 7.5, 150 mM KCl, 1 mM SAM, and 1 mM deuterium-labelled CTP (site-specifically labelled CTP contains deuterium at the following positions: 3'-2H,4'-2H,5'-2H2,5-2H-CTP or 2'-2H-CTP,3'-2H-CTP,4'-2H-CTP or 5'-2H2-CTP). In the Supplementary Information section ‘2'-deoxy-CTP vs deutero-CTP substrate specificity assays’ the sentence “Reactions of 100 μL total volume contained 100 μM rVIP, 50 mM HEPES pH 7.5, 150 mM KCl, 1 mM SAM, 1 mM deutero-CTP (2'-2H, 3'-2H, 4'-2H, 5'-2H2, and 5-2H CTP), and unlabeled 1 mM 2'-deoxy-CTP.” should have read: “Reactions of 100 μL total volume contained 100 μM rVIP, 50 mM HEPES pH 7.5, 150 mM KCl, 1 mM SAM, 1 mM deutero-CTP (3'-2H,4'-2H,5'-2H2,5-2H-CTP), and unlabelled 1 mM 2'-deoxy-CTP.” These errors have been corrected online.