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Updated: Jun 19, 2026
09:43
Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
ON HEMOCHROMOGEN
1Biophysical Laboratories of the Cancer Commission, Harvard University, Boston.
The Journal of General Physiology
|October 30, 2009
Summary
This study reveals that hemochromogens are iron-heme complexes. It demonstrates that globin protein can convert reduced heme into hemochromogen, with a higher capacity than other proteins like edestin or zein.
Area of Science:
- Biochemistry
- Molecular Biology
Background:
- Hemochromes are defined as iron-heme complexes bound to nitrogenous substances.
- An equilibrium exists between hemochrome, reduced heme, and the nitrogenous substance.
Purpose of the Study:
- To investigate the interaction between reduced heme and cyanide.
- To characterize the hemochromogen formed from hemoglobin.
- To compare the hemochromogen-forming capacity of globin with other proteins.
Main Methods:
- Formation of cyan-hemochromogen using reduced heme and cyanide.
- Preparation of hemochromogen from hemoglobin.
- Determination of hemochromogen-forming capacity of globin, edestin, and zein.
Main Results:
- Cyanide forms two compounds with reduced heme, including cyan-hemochromogen.
- Reduced heme exhibits high affinity for cyanide in alkaline solutions.
- Denatured globin can convert at least 10 molecules of reduced heme into hemochromogen.
- Globin demonstrates superior hemochromogen-forming capacity compared to edestin and zein.
Conclusions:
- Hemochromes are versatile iron-heme complexes.
- Globin possesses a significant capacity for hemochrome formation, exceeding that of other proteins studied.
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