Biological Rules and Mechanisms Governing the Nanofabrication of Highly Regular Mineralized Microlaminate Composites

摘要

We purified and characterized the proteins from the microlaminate abalone shell (a natural high performance armor with fracture toughness 3,000- fold greater than that of its mineral component alone) and 'flat pearl' and from sponge and diatom biosilicas. We then cloned and sequenced the cDNAs encoding these proteins, and used the resulting structural information, in concert with site- directed mutagenesis (genetic engineering) and real-time atomic force microscopy and other advanced imaging techniques to reveal the fundamental mechanisms by which the proteins control the mineral nucleation, growth and nanocomposite structures based on both silicon and calcium. Advanced imaging with AFM, XRD, SICM, EDAXAX and NMR was used to resolve the mechanisms controlling synthesis and shape in biomineralization and biomimetic synthesis, and details of the structure-directing organic-inorganic interfacial interactions. We then used this information to make useful new mineral-organic composite materials in vitro.