Native silaffins

Poulsen, N., Sumper, M. and Kroger, N. (2003) Silica formation in diatoms Characterization of native silaffin-2 and its role in silica morphogenesis. Proceedings of the National Academy of Sciences of the United States of America, 100, 12075-12080. 

The zwitterionic structure of the native silaffins leads to the self assembly of these molecules, which explains their extremely efficient induction of silica precipitation. Following up on this model, Sumperl l proposed, on the basis of simulations, a model that consists of multiple steps in which phase separation processes occur. At the initial stage phase separation of protein phase and silica permits the formation of the large, honeycomb structures, followed by several intermittent steps of silica formation - each mediated by phase separation processes to create smaller structures (see Fig. 9.18). 

Figure 19.7 Chemical background, (a) Schematic chemical structure of native silaffin-IA (pH 5). (Adapted from Ref. [56].) (b) Silicatein topology and the key role of the hydroxy group of serine-26 and the imidazole side chain of histidine-165 in the proposed mechanism for silicatein-mediated catalysis. (Adapted from Ref. [1001.)...

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