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Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate
Published on: April 24, 2018
ON PYRIDINE HEMOCHROMOGEN
1Biophysical Laboratory of the Cancer Commission, Harvard University, Boston.
The Journal of General Physiology
|October 30, 2009
Summary
Cyanide hemochromogen likely has one cyanide per heme. Pyridine hemochromogen studies are complicated by precipitation and aggregation, challenging previous conclusions about its structure.
Area of Science:
- Biochemistry
- Molecular Biology
Background:
- Hemochromes are derivatives of heme, a crucial component of hemoglobin.
- Pyridine hemochromogen and cyanide hemochromogen are specific types studied for their chemical properties.
Purpose of the Study:
- To clarify the stoichiometry of cyanide in cyanide hemochromogen.
- To re-evaluate the experimental conditions and conclusions regarding pyridine hemochromogen.
Main Methods:
- Analysis of chemical equilibrium involving pyridine and reduced heme.
- Assessment of precipitation and aggregation effects in hemochrome solutions.
Main Results:
- Evidence suggests one cyanide group per heme in cyanide hemochromogen.
- Identified precipitation of reduced heme and aggregation of pyridine hemochromogen as significant complicating factors.
- Demonstrated that R. Hill's previous experiments did not account for these complications.
Conclusions:
- The stoichiometry of cyanide hemochromogen is likely 1:1 (cyanide:heme).
- Previous conclusions regarding pyridine hemochromogen, specifically a 2:1 (pyridine:heme) ratio, are not supported due to unaddressed experimental complexities.
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