Turner, M. S., Agarwal, G., Jones, C. W., Wang, J. C., Kwong, S., Ferrone, F. A., Josephs, R. and Briehl, R. W.. (2006) Fiber depolymerization. BIOPHYSICAL JOURNAL, 91 (3). pp. 1008-1013. ISSN 0006-3495Full text not available from this repository.
Official URL: http://dx.doi.org/10.1529/biophysj.105.075333
Depolymerization is, by definition, a crucial process in the reversible assembly of various biopolymers. It may also be an important factor in the pathology of sickle cell disease. If sickle hemoglobin fibers fail to depolymerize fully during passage through the lungs then they will reintroduce aggregates into the systemic circulation and eliminate or shorten the protective delay ( nucleation) time for the subsequent growth of fibers. We study how depolymerization depends on the rates of end- and side-depolymerization, k(end) and k(side), which are, respectively, the rates at which fiber length is lost at each end and the rate at which new breaks appear per unit. ber length. We present both an analytic mean field theory and supporting simulations showing that the characteristic. ber depolymerization time tau = 1/root k(end)/k(side) depends on both rates, but not on the fiber length L, in a large intermediate regime 1 << k(side) L-2/k(end) << (L/d)(2), with d the fiber diameter. We present new experimental data which confirms that both mechanisms are important and shows how the rate of side depolymerization depends strongly on the concentration of CO, acting as a proxy for oxygen. Our theory remains rather general and could be applied to the depolymerization of an entire class of linear aggregates, not just sickle hemoglobin fibers.
|Item Type:||Journal Article|
|Subjects:||Q Science > QH Natural history > QH301 Biology|
|Journal or Publication Title:||BIOPHYSICAL JOURNAL|
|Number of Pages:||6|
|Page Range:||pp. 1008-1013|
Actions (login required)