The hemoglobin system of the primitive fish, Amia calva: isolation and functional characterization of the individual hemoglobin components
1976; Elsevier BV; Volume: 434; Issue: 1 Linguagem: Inglês
10.1016/0005-2795(76)90031-3
ISSN1878-1454
AutoresRoy E. Weber, Bolling Sullivan, Joseph Bonaventura, Celia Bonaventura,
Tópico(s)Neonatal Health and Biochemistry
ResumoBlood from the primitive holostean fish, the bowfin, Amia calva, contai ns 2 mo of ATP per mol of hemoglobin. The hemolysates contain at least five tetrameric hemoglobin components which differ in their oxygen affinities and their response to cofactors such as ATP. The binding of oxygen by each chromatographically isolated component, including a cathodal component,is influenced by pH and organic phosphates; there is no significant differentiation of function or structure as seen in trout and certain other fish hemolysates. Kinetic analyses of ligand binding indicate that the Bohr and Root effects of Amia calva hemoglobins are best explained by changes in both the “on” and “off” constants. At low pH, the increase in the “off” constant is smaller than for most other Root hemoglobins. The hemoglobin system of Amia calva is functionally undifferentiated and may be representative of the ancestral condition in teleosts.
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