Biosilica The enzymatically formed scaffold of siliceous sponge spicules

4 Biosilica The enzymatically formed scaffold of siliceous sponge spicules 

Initially, two different mechanisms had been proposed for silicatein reaction that might describe the condensation reaction of orthosihcic acid or silicon alkoxide (TEOS) substrates (Cha et al., 1999 Fairhead et al., 2008). These models explain the hydrolytic activity of silicatein toward its synthetic substrate, TEOS, or the initial formation of disiUcic acid from orthosilicic acid as the natural substrate, but none of them is able to desoibe the biocatalytic formation of the polymeric silica from its monomeric precursor(s). 

5 Self-healing property of silicatein embedded in spicuies 

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