
The Library
Anisotropy in sickle hemoglobin fibers from variations in bending and twist
Tools
Turner, Matthew S. , Briehl, R. W., Wang, J. C., Ferrone, F. A. and Josephs, R. (2006) Anisotropy in sickle hemoglobin fibers from variations in bending and twist. Journal of Molecular Biology, Vol.357 (No.5). pp. 1422-1427. doi:10.1016/j.jmb.2006.01.071 ISSN 0022-2836.
Research output not available from this repository.
Request-a-Copy directly from author or use local Library Get it For Me service.
Official URL: http://dx.doi.org/10.1016/j.jmb.2006.01.071
Abstract
We have studied the variations of twist and bend in sickle hemoglobin fibers. We find that these variations are consistent with an origin in equilibrium thermal fluctuations, which allows us to estimate the bending and torsional rigidities and effective corresponding material moduli. We measure bending by electron microscopy of frozen hydrated fibers and find that the bending persistence length, a measure of the length of fiber required before it starts to be significantly bent due to thermal fluctuations, is 130 mu m, somewhat shorter than that previously reported using light microscopy. The torsional persistence length, obtained by re-analysis of previously published experiments, is found to be only 2.5 mu m. Strikingly this means that the corresponding torsional rigidity of the fibers is only 6 x 10(-27) J m, much less than their bending rigidity of 5 x 10(-25) J m. For (normal) isotropic materials, one would instead expect these to be similar. Thus, we present the first quantitative evidence of a very significant material anisotropy in sickle hemoglobin fibers, as might arise from the difference between axial and lateral contacts within the fiber. We suggest that the relative softness of the fiber with respect to twist deformation contributes to the metastability of HbS fibers: HbS double strands are twisted in the fiber but not in the equilibrium crystalline state. Our measurements inform a theoretical model of the thermodynamic stability of fibers that takes account of both bending and extension/compression of hemoglobin (double) strands within the fiber. (c) 2006 Elsevier Ltd. All rights reserved.
Item Type: | Journal Article | ||||
---|---|---|---|---|---|
Subjects: | Q Science > QD Chemistry | ||||
Divisions: | Faculty of Science, Engineering and Medicine > Science > Life Sciences (2010- ) > Biological Sciences ( -2010) Faculty of Science, Engineering and Medicine > Science > Life Sciences (2010- ) Faculty of Science, Engineering and Medicine > Science > Physics |
||||
Journal or Publication Title: | Journal of Molecular Biology | ||||
Publisher: | Academic Press | ||||
ISSN: | 0022-2836 | ||||
Official Date: | 14 April 2006 | ||||
Dates: |
|
||||
Volume: | Vol.357 | ||||
Number: | No.5 | ||||
Number of Pages: | 6 | ||||
Page Range: | pp. 1422-1427 | ||||
DOI: | 10.1016/j.jmb.2006.01.071 | ||||
Status: | Peer Reviewed | ||||
Publication Status: | Published | ||||
Access rights to Published version: | Restricted or Subscription Access | ||||
Funder: | National Heart, Lung, and Blood Institute (US) (NHLBI) | ||||
Grant number: | HL 58512, HL 22654 |
Data sourced from Thomson Reuters' Web of Knowledge
Request changes or add full text files to a record
Repository staff actions (login required)
![]() |
View Item |