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09:43
Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
STUDIES ON INVERTEBRATE HEMOGLOBINS (ERYTHROCRUORINS).
1Department of Physiological Chemistry and Pharmacology, Yale University School of Medicine, New Haven.
The Journal of General Physiology
|October 30, 2009
Summary
This study compares invertebrate hemoglobins to vertebrate hemoglobin. Invertebrate hemoglobins share identical hemin with vertebrate hemoglobin and exhibit similar dissociation rates, suggesting functional similarities.
Area of Science:
- Biochemistry
- Comparative Physiology
- Molecular Biology
Background:
- Invertebrate hemoglobins, specifically erythrocruorins, are diverse in molecular weight.
- Understanding their properties aids in comparative analysis with vertebrate hemoglobin.
Purpose of the Study:
- To compare the physical-chemical properties of invertebrate hemoglobins (erythrocruorins) with vertebrate hemoglobin.
- To investigate the hemin identity and dissociation rates of selected invertebrate hemoglobins.
Main Methods:
- Studied high molecular weight erythrocruorins from Lumbricus terrestris and Nereis virens.
- Analyzed low molecular weight erythrocruorin from Glycera dibranchiata.
- Utilized DuBois reaction meter to measure dissociation rates (t50) of oxyhemoglobin.
Main Results:
- Hemin from Glycera dibranchiata erythrocruorin is identical to vertebrate hemoglobin hemin.
- Dissociation half-times (t50) for Glycera and human oxyhemoglobin were identical (0.027 seconds).
- Lumbricus terrestris erythrocruorin exhibited a slower dissociation half-time (0.070 seconds).
Conclusions:
- Invertebrate erythrocruorins share fundamental biochemical characteristics with vertebrate hemoglobins.
- Similar hemin structure and comparable dissociation rates suggest conserved functional aspects of oxygen transport across different species.
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