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Updated: Jun 19, 2026

Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source

Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source

Published on: February 7, 2013

A NEW GROWTH FACTOR REQUIRED BY CERTAIN HEMOLYTIC STREPTOCOCCI.

¹Laboratories of The Rockefeller Institute for Medical Research.

The Journal of Experimental Medicine

|October 30, 2009

Summary

Researchers discovered a novel growth factor crucial for hemolytic streptococci in Lancefield group A. This essential nutrient, found in liver, is water-soluble and non-dialyzable, aiding bacterial proliferation.

Area of Science:

Microbiology
Bacteriology
Biochemistry

Background:

Hemolytic streptococci of Lancefield group A are significant pathogens.
Understanding their nutritional requirements is key to controlling their growth.

Purpose of the Study:

To identify and characterize a new essential growth factor for Lancefield group A hemolytic streptococci.
To determine the physical and chemical properties of this novel factor.

Main Methods:

Demonstration of growth factor activity in liver extracts.
Fractionation of the active substance based on solubility and dialyzability.
Chemical treatment (alcohol, HCl) to alter dialyzability.

Main Results:

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Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source

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Published on: February 7, 2013

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues

Published on: February 19, 2019

A previously unidentified growth factor essential for Lancefield group A hemolytic streptococci was identified.

The factor is water-soluble, alcohol-insoluble, and non-dialyzable in its native state.

Treatment with strong alcohol and HCl rendered the factor dialyzable.

Conclusions:

A new, essential growth factor for hemolytic streptococci (Lancefield group A) has been characterized.
This factor's unique properties suggest it is distinct from previously known growth factors.
Further research is needed to fully elucidate the structure and function of this novel streptococcal growth factor.