Kurzfassung

Poriferan biosilicification represents a unique system to study the formation of complex biogenous silica structures, from genetic basis to macromolecular biomaterial. With the discovery of silicatein, which currently represents the only known natural biomineralizing enzyme, a versatile tool has become available to synthesize biosilica from soluble silicate under physiological conditions. Concurrently, the scaffold protein silintaphin-1 directs the assembly of enzymatically (via silicatein)...Poriferan biosilicification represents a unique system to study the formation of complex biogenous silica structures, from genetic basis to macromolecular biomaterial. With the discovery of silicatein, which currently represents the only known natural biomineralizing enzyme, a versatile tool has become available to synthesize biosilica from soluble silicate under physiological conditions. Concurrently, the scaffold protein silintaphin-1 directs the assembly of enzymatically (via silicatein) formed nanoparticles to needle-like skeletal elements (spicules). Conversely, the mechanisms behind the fusion of nanoparticles in vivo (i.e., biosintering) remain enigmatic. In vitro, recombinant silicatein and silintaphin-1 self-assemble to filaments (similar to those found within spicules) that template the assembly of nanoparticles to rudimentary spicules. Nevertheless, the synthetic procedures applied so far lack morphological control of the polymeric products. In addition, biosintering processes have not been harnessed in vitro. Hence, the proposed projects aims to identify those molecules that facilitate biosintering of silica-nanoparticles and are crucially involved in morphogenesis of the elaborately shaped spicules with complex symmetries. These "silica-proteins" (associated with silicatein and silica), then, will be used to create in vitro structured silica:protein hybrid materials, whose physical properties and mechanical aspects will be analyzed subsequently. Concurrently, they are an excellent model to study biosintering.» weiterlesen» einklappen