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Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source
06:37

Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source

Published on: February 7, 2013

Hemin utilization is related to virulence of Streptococcus pneumoniae

S S Tai1, C J Lee, R E Winter

  • 1Department of Microbiology, Howard University, Washington, D.C. 20059.

Infection and Immunity
|December 1, 1993
PubMed

Insights

Streptococcus pneumoniae acquires iron from hemoglobin and hemin, not siderophores, to cause infections. Impaired iron uptake reduces its virulence in animal models.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Bacterial Pathogenesis

Background:

  • Streptococcus pneumoniae causes severe infections like pneumonia and meningitis.
  • Understanding how this bacterium obtains iron is crucial for developing treatments, especially under low-iron conditions found in the host.

Purpose of the Study:

  • To investigate the mechanisms Streptococcus pneumoniae uses to acquire iron.
  • To determine if S. pneumoniae produces siderophores or utilizes host iron compounds.

Main Methods:

  • Tested for siderophore production using chemical and biological assays.
  • Assessed growth of S. pneumoniae with various iron-containing compounds (hemin, hemoglobin, lactoferrin, transferrin) in iron-limited media.
  • Isolated and characterized a mutant with impaired hemin utilization.

Main Results:

  • Siderophore production was not detected in S. pneumoniae.
  • Hemin and hemoglobin supported robust growth, while lactoferrin and transferrin did not.
  • A hemin utilization mutant exhibited reduced virulence in experimental animals.

Conclusions:

  • Streptococcus pneumoniae primarily utilizes hemin and hemoglobin for iron acquisition.
  • Siderophore-independent iron uptake is key for S. pneumoniae pathogenesis.
  • Hemin utilization is essential for the full virulence of S. pneumoniae.

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