Metal In The Mussel That Gives Mussels Their Muscle Power

[n2doc]

(Love that title!)

ScienceDaily (Apr. 13, 2009) — Researchers in California are reporting for the first time that metals are key ingredients that give the coatings of anchoring byssal threads of marine mussels their amazing durability.

The study could lead to the design of next-generation coatings for medical and industrial applications, including surgical coatings that protect underlying tissues from abrasion and also life-threatening bacterial infections, the researchers say.
In the new study, Herbert Waite and colleagues point out that many existing coatings are severely limited by the materials they cover. A rubber band dipped in molten wax is a good case in point. Once hardened at room temperature, the wax is several times harder and stiffer than the underlying rubber, but even moderate extension shatters the wax. Scientists have been trying for years to develop robust coatings for soft or delicate underlying materials.
Until recently, however, scientists knew little about the chemical mechanisms that allow mussels to coat the tendon-like fibers in byssal threads with a material that is both hard and extensible.

http://www.sciencedaily.com/releases/2009/04/090413083315.htm

[hunter]

1. Iron and calcium...

That's one of those interesting little tidbits that's going to be floating around in the heads of material scientists, and it's very likely something very important will come out of it.

Abstract: The cuticle of mussel byssal threads is a robust natural coating that combines high extensibility with high stiffness and hardness. In this study, fluorescence microscopy and elemental analysis were exploited to show that the 3,4-dihydroxyphenyl-l-alanine (dopa) residues of mussel foot protein-1 colocalize with Fe and Ca distributions in the cuticle of Mytilus galloprovincialis mussel byssal threads. Chelated removal of Fe and Ca from the cuticle of intact threads resulted in a 50% reduction in cuticle hardness, and thin sections subjected to the same treatment showed a disruption of cuticle integrity. Dopa-metal complexes may provide significant interactions for the integrity of composite cuticles deformed under tension.

http://dx.doi.org/10.1021/la8027012