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Updated: May 29, 2026
06:37
Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source
Published on: February 7, 2013
Structural basis for hemoglobin capture by Staphylococcus aureus cell-surface protein, IsdH.
Kaavya Krishna Kumar1, David A Jacques1, Gleb Pishchany2
1School of Molecular Bioscience, University of Sydney, New South Wales 2006, Australia.
The Journal of Biological Chemistry
|September 16, 2011
Summary
Pathogens like Staphylococcus aureus capture host hemoglobin (Hb) for iron. This study reveals the structure of Hb bound to a bacterial protein, offering targets for new antibacterial drugs.
Area of Science:
- Microbiology
- Structural Biology
- Infectious Diseases
Background:
- Pathogens require host iron for infection.
- Mammalian hemoglobin (Hb) is a major iron reservoir.
- Pathogens utilize Hb-binding proteins to acquire iron.
Purpose of the Study:
- To elucidate the mechanism of hemoglobin capture by Staphylococcus aureus.
- To determine the structural basis of Hb-IsdH interaction.
- To explore Hb sequence as a factor in infection susceptibility.
Main Methods:
- X-ray crystallography to determine the structure of Hb bound to IsdH.
- Site-directed mutagenesis of Hb to assess binding and utilization.
- Bacterial growth assays to measure iron acquisition from Hb.
Main Results:
- The first structure of a hemoglobin-capture complex involving IsdH from S. aureus was determined.
- Specific surface residues on Hb are critical for binding to IsdH.
- Reduced Hb binding to IsdH impairs S. aureus iron acquisition and growth.
Conclusions:
- Staphylococcus aureus specifically recognizes and captures host hemoglobin via the IsdH protein.
- Hb sequence variation can influence host susceptibility to S. aureus infection.
- Inhibiting Hb binding presents a potential strategy for developing novel antibacterial therapies.
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