These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Titration of the carboxyhemoglobin tetramer-dimer equilibrium by inositol hexaphosphate.
    Author: White SL.
    Journal: J Biol Chem; 1976 Aug 10; 251(15):4763-9. PubMed ID: 947909.
    Abstract:
    The results of a series of light scattering experiments of the reaction of inositol hexaphosphate (at pH 7.0) over 6 orders of magnitude of concentration (10(-8) to 10(-2) M) with carboxyhemoglobin indicates that there is a shift in the tetramer-dimer equilibrium towards the tetramer, reaching a maximum effect at 0.1 mM inositol hexaphosphate. Raising the phosphate concentration beyond this latter value promotes dissociation to dimers. However, in this range some of the dissociation of carboxyhemoglobin was undoubtedly due to the increase in ionic strength from the inositol hexaphosphate ion. If the effect of ionic strength is allowed for by classical Debye-Hückel theory, one- and possibly two-phosphate binding sites per dimer can be detected. (Approximate association constant is 8000 M-1 for a single site at 0.1 ionic strength). The location of such sites is considered to lie near the dissociable plane of the hemoglobin tetramer and possibly to include half of the residues that bind inositol hexaphosphate in the tetramer.
    [Abstract] [Full Text] [Related] [New Search]