The authors regret that there were developments in affiliations and funding acknowledgements during the time from initial submission to final acceptance which have not been reported correctly. Specifically, the affiliations of the co-authors R. Chitchyan, M. Montakhabi, M. Andoni, and I. Scott were not up to date. The corrected affiliations of all authors are as follows. Concerning funding acknowledgements, the information of M. Andoni, V. Robu, and I.J. Scott were not up to date. In addition to the provided information, the following to fundings should be acknowledged. Merlinda Andoni received funding from the EPSRC DecarbonISation PAThways for Cooling and Heating (DISPATCH) project (grant number EP/V042955/1) and the InnovateUK Responsive Flexibility (ReFLEX) project [ref: 104780]. Valentin Robu was supported by the project “TESTBED2: Testing and Evaluating Sophisticated information and communication Technologies for enaBling scalablE smart griD Deployment”, funded by the European Union Horizon2020 Marie Skłodowska-Curie Actions (MSCA) [Grant agreement number: 872172]. Ian Scott was supported by national funds through FCT (Fundação para a Ciência e a Tecnologia), under the project - UIDB/04152/2020 - Centro de Investigação em Gestão de Informação (MagIC)/NOVA IMS. The authors would like to apologise for any inconvenience caused.

The biogeochemical cycle of iron is intricately linked to numerous element cycles. Although biological processes that catalyze the reductive side of the iron cycle are established, little is known about microbial oxidative processes on iron cycling in sedimentary environments—resulting in the formation of iron oxides. Here we show that a potential source of sedimentary iron oxides originates from the metabolic activity of iron-oxidizing bacteria from the class Zetaproteobacteria, presumably enhanced by burrowing animals in coastal sediments. Zetaproteobacteria were estimated to be a global total of 10²⁶ cells in coastal, bioturbated sediments, and predicted to annually produce 8 × 10¹⁵ g of Fe in sedimentary iron oxides—55 times larger than the annual flux of iron oxides deposited by rivers. These data suggest that iron-oxidizing Zetaproteobacteria are keystone organisms in marine sedimentary environments—despite their low numerical abundance—yet exert a disproportionate impact via the rejuvenation of iron oxides.