Embedded proteins and sacrificial bonds provide the strong adhesive properties of gastroliths.
The adhesive properties of gastroliths from a freshwater crayfish (Cherax quadricarinatus) were quantified by colloidal probe atomic force microscopy (AFM) between heavily demineralized gastrolith microparticles and gastrolith substrates of different composition. Combined AFM and transmission electron microscopy studies demonstrated that the sequential detachment and large adhesion energies that characterise the adhesive behaviour of a native gastrolith substrate are dominated by sacrificial bonds between chitin fibres and between chitin fibres and CaCO(3). The sacrificial bonds were shown to be strongly related to the gastrolith proteins and when the majority of these proteins were removed by ethylenediaminetetraacetic acid (EDTA), the sequential detachment disappeared and the adhesive energy was reduced by more than two orders of magnitude.
KTH Royal Institute of Technology, Department of Chemistry, Surface and Corrosion Science, SE-100 44 Stockholm, Sweden.
Esben
E
Thormann
Hiroyasu
H
Mizuno
Kjell
K
Jansson
Niklas
N
Hedin
M Soledad
MS
Fernández
José Luis
JL
Arias
Mark W
MW
Rutland
Ranjith Krishna
RK
Pai
Lennart
L
Bergström
D000818:Animals; D003400:Astacoidea / Q000378:metabolism; D002119:Calcium Carbonate / Q000737:chemistry; D002686:Chitin / Q000737:chemistry / Q000378:metabolism; D004492:Edetic Acid / Q000737:chemistry; D018625:Microscopy, Atomic Force; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*
D011506:Proteins; D002686:Chitin; D004492:Edetic Acid; D002119:Calcium Carbonate