A Delicate Balance between Bacterial Iron and Reactive Oxygen Species Supports Optimal C. elegans Development

UMMS Affiliation

Program in Systems Biology; Program in Molecular Medicine; Graduate School of Biomedical Sciences

Publication Date


Document Type



Bacteria | Biochemical Phenomena, Metabolism, and Nutrition | Cell Biology | Cellular and Molecular Physiology | Developmental Biology | Genetic Phenomena | Genetics and Genomics | Systems Biology


Iron is an essential micronutrient for all forms of life; low levels of iron cause human disease, while too much iron is toxic. Low iron levels induce reactive oxygen species (ROS) by disruption of the heme and iron-sulfur cluster-dependent electron transport chain (ETC). To identify bacterial metabolites that affect development, we screened the Keio Escherichia coli collection and uncovered 244 gene deletion mutants that slow Caenorhabditis elegans development. Several of these genes encode members of the ETC cytochrome bo oxidase complex, as well as iron importers. Surprisingly, either iron or anti-oxidant supplementation reversed the developmental delay. This suggests that low bacterial iron results in high bacterial ROS and vice versa, which causes oxidative stress in C. elegans that subsequently impairs mitochondrial function and delays development. Our data indicate that the bacterial diets of C. elegans provide precisely tailored amounts of iron to support proper development.


C. elegans, E. coli, diet, electron transport chain, flux balance analysis, iron, metabolic network modeling, metabolism, reactive oxygen species

DOI of Published Version



Cell Host Microbe. 2019 Sep 11;26(3):400-411.e3. doi: 10.1016/j.chom.2019.07.010. Epub 2019 Aug 20. Link to article on publisher's site

Journal/Book/Conference Title

Cell host and microbe

Related Resources

Link to Article in PubMed

PubMed ID