Copper Homeostasis Mechanisms in Bacterial Systems

Copper is an indispensable cofactor for enzymes involved in respiration, oxidative stress defence and electron transport, yet its redox activity renders it toxic when unshielded. To balance acquisition and toxicity, bacteria employ coordinated networks of importers, chaperones, storage proteins and efflux pumps. Cytoplasmic sensors detect intracellular copper levels and regulate gene expression, while periplasmic or membrane-associated systems monitor extracytoplasmic pools. Dedicated copper chaperones escort Cu(I) to cuproproteins or to efflux ATPases, preventing harmful Fenton chemistry. Two-component regulatory circuits and specialised transcription factors adjust transporter and enzyme expression in response to environmental fluctuations. Structural studies of copper-binding domains and four-helix bundle storage proteins have revealed how bacteria tune affinity and capacity for Cu(I) coordination. Together, these mechanisms underpin bacterial survival under copper stress, influence metal cycling in natural and engineered ecosystems, and illuminate targets for antimicrobial strategies that exploit copper toxicity.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Copper Homeostasis Mechanisms in Bacterial Systems publication trend

The graph below shows the total number of articles in copper homeostasis mechanisms in bacterial systems across all publications each year (not limited to Nature Index journals).

Technical terms

Cuproprotein: A protein that requires copper as a catalytic cofactor for its biological activity.

Two-component regulatory system: A signal transduction module comprising a membrane sensor histidine kinase and a cytoplasmic response regulator that controls gene expression.

Translational control: Regulation of gene expression at the level of mRNA translation, often via structural elements or ribosomal pausing.

Efflux system: A membrane-spanning transporter complex that exports excess metal ions or toxic compounds out of the cell.

Chaperone: A protein that assists folding or prevents aggregation of client proteins, especially under stress conditions.

Periplasm: The space between the inner and outer membranes in Gram-negative bacteria, containing enzymes and binding proteins for metal sensing.

References

1. Metabolic Sensing of Extracytoplasmic Copper Availability via Translational Control by a Nascent Exported Protein. mBio (2023).
2. The Sensory Histidine Kinase CusS of Escherichia coli Senses Periplasmic Copper Ions. Microbiology Spectrum (2023).
3. Copper Induces Protein Aggregation, a Toxic Process Compensated by Molecular Chaperones. mBio (2022).
4. Important Structural Features of Thiolate-Rich Four-Helix Bundles for Cu(I) Uptake and Removal. Inorganic Chemistry (2023).
5. Cu Homeostasis in Bacteria: The Ins and Outs. Membranes (2020).