Mitochondrial COA7 is a heme-binding protein with disulfide reductase activity, which acts in the early stages of complex IV assembly

This study was funded by the Australian Research Council (DP140102746 and FT180100397 to M.J.M. and DP220102030 to M.J.M. and M.T.R.) , the National Health and Medical Research Council (GNT1165217 to M.T.R. and M.J.M., GNT1140906 and GNT1140851 to D.A.S., and GNT2010149 to L.E.F.) , and an Australian Government Research Training Program Scholarship to S.M. L.E.F. also acknowledges support from the Mito Foundation. Part of this study was carried out using the MX2 beamline at the Australian Synchrotron, which is part of the Australian Nuclear Science and Technology Organisation (ANSTO) , and made use of the Australian Cancer Research Foundation (ACRF) detector. We thank the beamline staff for their enthusiastic and professional support, Dr. Yee-Foong Mok at the Melbourne Protein characterization facility, the Bio21 Molecular Science and Biotechnol-ogy Institute for performing the AUC experiments and data analyses, the Bio21 Mass Spectrometry and Proteomics Facility for the provision of instru-mentation, training, and technical support, Daniel Machell for PyMOL and coding assistance, Dr. Katie Ganio and Prof. Christopher McDevitt for the ICP-MS analysis, and Mrs. Mahnaz Dideh Var for her extraordinary support with the structural biology aspects of this study. We thank the reviewers for their constructive comments. Schematics were created using Biorender.com .