Abstract
The surface layer (S-layer) of Deinococcus radiodurans composed of single protein, that molecular weight is about 126 kDa. In this article, we got some investigations about properties of the D. radiodurans IR S-layer protein (SLP) self-assembled on native silicon wafer. We also found great potential of D. radiodurans IR SLP that apply in the nanobiotechnology. We had demonstrate the capacity of D. radiodurans IR SLP self-assembled on native silicon wafer in low concentration hydrogen-bond-breaking agent which had added in a cell wall preparation to extract SLP. In optical microscopy (OM) and confocal laser scanning microscopy (confocal), we found self-assembled products with two structures on wafer：(1) Large-scale self-assembled film (large-scale SAF). (2) Multi-layered self-assembled film (multi-layered SAF). Atomic force microscopy (AFM) studies show that surface morphology of SAF was composed of uniform particles. In applications, we used different buffer systems to directly synthesize Ag nanowire and variant Ag nanostructures on D. radiodurans IR SLP functionalized wafer. In improved systems, we can get dispersed Ag nanowire on wafer with average length=90 ± 6.7 μm (aspect ratio ~1000). In another system, we can adjust pH to fabricate variant Ag nanostructures on SAF.