Robust cross-links in molluscan adhesive gels: testing for contributions from hydrophobic and electrostatic interactions.

Autor: Smith AM; Department of Biology, Ithaca College, Ithaca, New York 14850, USA. asmith@ithaca.edu, Robinson TM, Salt MD, Hamilton KS, Silvia BE, Blasiak R
Jazyk: angličtina
Zdroj: Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology [Comp Biochem Physiol B Biochem Mol Biol] 2009 Feb; Vol. 152 (2), pp. 110-7. Date of Electronic Publication: 2008 Oct 15.
DOI: 10.1016/j.cbpb.2008.10.004
Abstrakt: The cross-linking interactions that provide cohesive strength to molluscan adhesive gels were investigated. Metal-based interactions have been shown to play an important role in the glue of the slug Arion subfuscus (Draparnaud), but other types of interactions may also contribute to the glue's strength and their role has not been investigated. This study shows that treatments that normally disrupt hydrophobic or electrostatic interactions have little to no effect on the slug glue. High salt concentrations and non-ionic detergent do not affect the solubility of the proteins in the glue or the ability of the glue proteins to stiffen gels. In contrast, metal chelation markedly disrupts the gel. Experiments with gel filtration chromatography identify a 40 kDa protein that is a central component of the cross-links in the glue. This 40 kDa protein forms robust macromolecular aggregations that are stable even in the presence of high concentrations of salt, non-ionic detergent, urea or metal chelators. Metal chelation during glue secretion, however, may block some of these cross-links. Such robust, non-specific interactions in an aqueous environment are highly unusual for hydrogels and reflect an intriguing cross-linking mechanism.
Databáze: MEDLINE