Abstract
The effects of pH, organic phosphates (2,3-diphospho- glycerate), and
temperature on the functional properties of both adult and fetal
hemoglobin Sassari alpha (Asp-126 --> His) have been studied. The
functional properties of the adult variant are characterized by the
following: (i) an oxygen affinity higher than that of normal HbA in all
the experimental conditions used; (ii) a dramatic reduction of homotropic interactions (n(50) very close to unity); and (iii) a significant decrease of the effect of 2,3-diphosphoglycerate, which is 35% lower than that observed on HbA.
The fetal variant shows an increased oxygen affinity compared with
normal HbF and an almost abolished heme-heme interaction. The molecular
basis of these functional differences is discussed in terms of the
possible role played by the substitution of alpha (Asp-26 --> His) on the stability of the R state of the molecule due to a decreased
interaction at the level of alpha(1) alpha(2) contact.
Lingua originale | Inglese |
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pagine (da-a) | 18338-18342 |
Numero di pagine | 5 |
Rivista | THE JOURNAL OF BIOLOGICAL CHEMISTRY |
Volume | 269 |
Stato di pubblicazione | Pubblicato - 1994 |
Keywords
- ALPHA