|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
First published online November 30, 2007
Journal of Experimental Biology 210, 4307-4318 (2007)
Published by The Company of Biologists 2007
doi: 10.1242/jeb.009753
Holdfast heroics: comparing the molecular and mechanical properties of Mytilus californianus byssal threads
Department of Molecular, Cellular, and Developmental Biology, University of California at Santa Barbara (UCSB), Santa Barbara, CA 93106, USA
* Author for correspondence (e-mail: harringt{at}lifesci.ucsb.edu)
Accepted 2 October 2007
The marine mussel Mytilus californianus Conrad inhabits the most wave-exposed regions of the rocky intertidal by dint of its extraordinary tenacity. Tenacity is mediated in large part by the byssus, a fibrous holdfast structure. M. californianus byssal threads, which are mechanically superior to the byssal threads of other mytilids, are composed almost entirely of a consortium of three modular proteins known as the preCols. In this study, the complete primary sequence of preCols from M. californianus was deduced and compared to that of two related species with mechanically inferior byssal threads, M. edulis Linnaeus and M. galloprovincialis Lamarck in order to explore structure–function relationships.
The preCols from M. californianus are more divergent from the other two species than they are from one another. However, the degree of divergence is not uniform among the various domains of the preCols, allowing us to speculate on their mechanical role. For instance, the extra spider silk-like runs of alanine-rich sequence in the flanking domains of M. californianus may increase crystalline order, enhancing strength and stiffness. Histidine-rich domains at the termini, in contrast, are highly conserved between species, suggesting a mechanical role common to all three. Mechanical testing of pH-treated and chemically derivatized distal threads strongly suggests that histidine side chains are ligands in reversible, metal-mediated cross-links in situ. By combining the mechanical and sequence data, yield and self-healing in the distal region of threads have been modeled to emphasize the intricate interplay of enthalpic and entropic effects during tensile load and recovery.
Key words: mussel, byssus, self-healing, histidine–metal, collagen
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati
Twitter What's this?
Related articles in JEB:
This article has been cited by other articles:
![]() |
J. Sagert and J. H. Waite Hyperunstable matrix proteins in the byssus of Mytilus galloprovincialis J. Exp. Biol., July 15, 2009; 212(14): 2224 - 2236. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Pearce and M. LaBarbera A comparative study of the mechanical properties of Mytilid byssal threads J. Exp. Biol., May 15, 2009; 212(10): 1442 - 1448. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Holten-Andersen and J. H. Waite Mussel-designed Protective Coatings for Compliant Substrates Journal of Dental Research, August 1, 2008; 87(8): 701 - 709. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Phillips MUSSELS TAKE THE STRAIN J. Exp. Biol., December 15, 2007; 210(24): i - ii. [Full Text] [PDF] |
||||