Abstract
We have demonstrated the in vitro self-assembly capacity of Deinococcus radiodurans IR S-layer proteins (SLPs) by using a protocol involving removing of a hydrogen-bond-breaking agent that had added in a cell wall preparation to extract protein molecules of interest. The resulted self-assemblies (SAs) were micron-scale sheet structures when observed under light and electronic microscope. Also observed was the regular pattern on SAs’ surface (TEM) and multilayer structures (field-emission SEM). Furthermore, we determined the SAs’ particle size distribution (COULTER® Multisizer II) in the course of SAs formation. These results suggested that the self-assembly was time- and temperature-dependent and was mainly due to ~100 kD cell-wall proteins (SDS-PAGE). Coulter size analysis could be of potential application in the study of mechanism of self-assembly in particular and in the field of nanotechnology in general.