Human hemoglobin, properties

Mieyal JJ, Acherman RS, Blumer JL, Freeman LS (1976) Characterization of enzyme-like activity of human hemoglobin. Properties of the hemoglobin-P-450 reductase-coupled aniline hydroxylase system. J Biol Chem 251 3436-3441... 

From this type of analysis, one would conclude that t must be approximately 28 for a 10% reduction in protomer to cause a 95% reduction in the nucleus concentration. This is a rather startling apparent reaction order even assuming infinite cooperativity between protomers. It is recalled that Hofrichter et al. (1974) found from a similar analysis of the rate of nucleation of human hemoglobin S (HbS) at 30 C that the apparent reaction order for the nucleation of HbS aggregation was about 32. Of course, such analyses are not fully justifiable because one may not assume ideality in the solution properties of biopolymers at high concentrations, particularly at 200 mg/ml in the case of hemoglobin. The computation for the case of tubulin polymerization does, nonetheless, emphasize that nucleation would be an especially cooperative event if only tubulin, and not ring structures, played the active role in nuclei formation. 

The Human Hemoglobins Their Properties and Genetic Control Harvey A. Itano... 

One would conclude that / must approximately equal 28 for this process Hofrichter et al found a similar behavior in nucleation of human hemoglobin S (HbS) the apparent reaction order for the nucleation of HbS aggregation was about 32 (See Hemoglogin S Polymerization). Of course, such analyses are not fully justifiable, because one cannot assume ideality in the solution properties at high protein concentrations (See Molecular Crowding). 

The structural and functional properties of human hemoglobin (Hb) have been the subject of study for decades, stimulated by the intriguing characteristic of positive cooperativity. How do the four subunits that compose the Hb tetramer communicate with one another The answer to this question has been sought primarily through the comparison of deoxy with oxy Hb. However, to understand the molecular mechanism of a chemical reaction, it is necessary to characterize the intermediate(s) of the process, and the reaction of Hb with O2 is no exception. 

B51. Bookchin, R. M., Nagel, R. L., and Ranney, H. M., Structure and properties of hemoglobin Cnariem, a human hemoglobin variant with amino acid substitutions in 2 residues of the /3-polypeptide chain. J. Biol. Chem. 242, 248-255 (1967). 

H18. Holmquist, W. R., and Sehroeder, W. A., Properties and partial characterization of adult human hemoglobin Aio. Biochim. Biophys. Acta 82, 639-641 (1964). 

T9. Tomita, S., and Riggs, A., Effects of partial deuteration on the properties of human hemoglobin. J. Biol. Chem. 245, 3104-3109 (1970). 

Amiconi G., Zolla L., Vecchini P., Brunori M., Antonini E. The effect of macromolecular polyanions on the functional properties of human hemoglobin. Eur. J. Biochem. 1977 76 339-343. 

Sickle-cell-anemia hemoglobin is closely similar to normal adult human hemoglobin in most of its properties. The two proteins have approximately the same sedimentation and diffusion constants,... 

In a recent study Chiancone et al. [469] investigate the Cl binding to the two main hemoglobin components in trout blood, Hb-Trout I and Hb-Trout IV. These two hemoglobins from the species Salmo irideus are electrophoretically different and may be separated. The two components have strikingly different functional properties. A Root effect (the equivalent of the Bohr effect for human hemoglobin),... 

After these reports there were many attempts to administer hemoglobin solutions to humans. Many of these patients did well, but others demonstrated hypertension, bradycardia, oliguria, and even anaphylaxis. These untoward effects were not correlated with specific biochemical properties of the solutions themselves. 

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