![]()
|
|
||||||||
J. Biol. Chem., Vol. 259, Issue 11, 7169-7177, 06, 1984
J Eisinger, J Flores and RM Bookchin
The effect of deoxygenation on the amount of hemoglobin (Hb) proximal to
the membranes of intact, density-fractionated normal (AA) and sickle (SS)
red cells was studied by estimating resonance energy transfer efficiencies
from fluorescent probes, 12-(9-anthroyloxy)stearic acid or
2-(9-anthroyloxy)stearic acid, in the outer lipid layer to cytoplasmic
hemes. For each density fraction, heme concentrations at the cytosol-
membrane interface (hb) were derived from the probe decay rates for ghosts
and intact cells, measured by front-face fluorometry, and compared with
mean cell heme concentrations (hc). With AA cells, hb/hc varied little with
cell density; a 33% drop in hb on deoxygenation is attributable to organic
phosphate binding to deoxy-Hb. With oxy-SS cells, hb/hc increased with cell
density to twice the values for AA cells, but SS ghosts showed no evidence
of increased probe quenching by membrane-bound Hb. On deoxygenation, hb for
each SS density fraction fell (reversibly) to one-third the oxy value. The
finding that deoxy- HbS withdraws from the membrane bilipid layer much more
than deoxy-HbA is consistent with evidence for an increased net negative
charge on deoxy-HbS polymers and/or the suggestion that the cytoskeleton,
readily penetrated by monomeric Hb, presents a barrier to polymeric HbS.
Membrane-associated HbS is therefore thought to play an unimportant role in
polymerization.
The cytosol-membrane interface of normal and sickle erythrocytes. Effect of hemoglobin deoxygenation and sickling
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
J. Evans, W. Gratzer, N. Mohandas, K. Parker, and J. Sleep Fluctuations of the Red Blood Cell Membrane: Relation to Mechanical Properties and Lack of ATP Dependence Biophys. J., May 15, 2008; 94(10): 4134 - 4144. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |