Tracking iron-associated proteomes in pathogens by a fluorescence approach

Area of Science:

• Microbiology
• Biochemistry
• Structural Biology

Background:

• Porphyromonas gingivalis is a key oral anaerobic bacterium implicated in human periodontitis, a condition affecting a significant portion of the global adult population.
• Understanding iron homeostasis is crucial for developing strategies against bacterial pathogens.

Purpose of the Study:

• To identify iron-associated proteins in Porphyromonas gingivalis.
• To demonstrate the utility of a novel fluorescent probe for metalloproteomics.
• To provide structural insights into probe-protein interactions.

Main Methods:

• Utilized the membrane-permeable fluorescent probe Fe-TRACER for identifying iron-associated proteins.
• Employed fluorescence imaging, proteomics, and bioinformatics.
• Determined the X-ray structure of the fluorescent probe-bound transferrin.

Main Results:

• Successfully identified 17 iron-associated proteins in Porphyromonas gingivalis.
• Demonstrated specific binding of the Fe-TRACER probe to iron-associated proteins, exemplified by transferrin.
• Obtained the X-ray structure of the fluorescent probe-transferrin complex.

Conclusions:

• The study provides a foundation for understanding iron homeostasis in pathogenic bacteria.
• The integrated approach of fluorescence imaging, proteomics, and bioinformatics is effective for metalloproteome analysis.
• This methodology can be extended to investigate other metalloproteomes in microbial systems.