Correction to: Nature Metabolism https://doi.org/10.1038/s42255-019-0120-1, published online 7 October 2019.

In the version of this article initially published, in Fig. 2c,d and Extended Data Fig. 3a,b, the y axes of the dNTP plots were mislabelled. In Fig. 2c,d, the y-axis labels read ‘[dNTP] relative’ but should have read ‘[dNTP] fmol per μg mitochondrial protein’. In Extended Data Fig. 3a,b, the y-axis units read ‘[dNTP] uM’ but should have read ‘[dNTP] nmol/million cells’. The errors have been corrected in the HTML and PDF versions of the article.