Correction to: Nature Reviews Microbiology https://doi.org/10.1038/s41579-022-00687-z, published online 07 February 2022.

In Figure 4 of the original article, one of the arrows was erroneously labelled Nitrification instead of Low O2. This has now been corrected in all versions of the Review. The publisher apologizes to the authors and to readers for this error.