Biochemical Characterization of Barnacle Cement

The extreme resistance of the hardened cement toward salt solutions, dilute acid, and alkali suggested that hydrogen or salt bonds were too weak to be the main crosslinking mechanisms. Disulfide bonds were also precluded due to the resistance of the adhesive to thioglycolate (see Ref [12]). 

The authors [18] additionally found a triplet of proteins, which further broke down into subunits under denaturing conditions. It was suggested that this protein complex in its quaternary structure formed by small subunits is equivalent to the globular cement structures detected previously [2] (see below). 

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