Abstract
The functional and spectroscopic (EPR and absorbance) properties of the adult loggerhead sea turtle (Caretta caretta) hemoglobin have been studied with special reference to the action of allosteric effectors and temperature. Present results indicate that turtle Hb displays a very low O2 affinity and a very small sensitivity to allosteric effectors and temperature. Furthermore, the amplitude of the Bohr effect for O2 binding is strongly reduced. In parallel, EPR and absorbance spectroscopic properties of the nitrosylated derivative of turtle Hb suggest that the hemoprotein is in low-affinity conformation, even in the absence of allosteric effectors. These findings suggest the existence of unusual molecular mechanisms modulating the basic reaction of Hb with O2, which may be linked to specific physiological needs related to the diving behavior of the turtle.
Original language | English |
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Pages (from-to) | 129-133 |
Number of pages | 5 |
Journal | Biochimica et Biophysica Acta (BBA)/Protein Structure and Molecular |
Volume | 1159 |
Issue number | 2 |
DOIs | |
Publication status | Published - Sep 23 1992 |
Keywords
- (C. caretta)
- (Sea turtle)
- Absorbance
- Allosteric effector
- EPR
- Hemoglobin
- Temperature effect
ASJC Scopus subject areas
- Biochemistry
- Biophysics
- Molecular Biology
- Structural Biology
- Medicine(all)