Effects of iron concentration and DFB (Desferrioxamine-B) on transcriptional profiles of an ecologically relevant marine bacterium

PLoS One. 2023 Dec 15;18(12):e0295257. doi: 10.1371/journal.pone.0295257. eCollection 2023.

Abstract

Research into marine iron cycles and biogeochemistry has commonly relied on the use of chelators (including siderophores) to manipulate iron bioavailability. To test whether a commonly used chelator, desferrioxamine B (DFB) caused effects beyond changing the iron-status of cells, cultures of the environmentally relevant marine heterotrophic bacterium, Ruegeria pomeroyii, were grown in media with different concentrations of iron and/or DFB, resulting in a gradient of iron availability. To determine how cells responded, transcriptomes were generated for cells from the different treatments and analyzed to determine how cells reacted to these to perturbations. Analyses were also performed to look for cellular responses specific to the presence of DFB in the culture medium. As expected, cells experiencing different levels of iron availability had different transcriptomic profiles. While many genes related to iron acquisition were differentially expressed between treatments, there were many other genes that were also differentially expressed between different sample types, including those related to the uptake and metabolism of other metals as well as genes related to metabolism of other types of molecules like amino acids and carbohydrates. We conclude that while DFB certainly altered iron availability to cells, it also appears to have had a general effect on the homeostasis of other metals as well as influenced metabolic processes outside of metal acquisition.

MeSH terms

  • Chelating Agents
  • Deferoxamine* / metabolism
  • Deferoxamine* / pharmacology
  • Iron* / metabolism
  • Metals
  • Siderophores / genetics

Substances

  • Iron
  • Deferoxamine
  • Siderophores
  • Metals
  • Chelating Agents

Grants and funding

We thank two outstanding undergraduate students, Kellina Morris and Emlyn Hammer, for their efforts in conducting some of these experiments. We also thank Alison Buchan for providing the Roseobacter strains for our experiments and analyses. This work was supported in part by a grant from the National Science Foundation (OCE- 1829641). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.