Disulfide bond: dramatically enhanced assembly capability and structural stability of tobacco mosaic virus nanorods.

Tobacco mosaic virus (TMV) is a classical viral nanoarchitecture that has been extensively employed as a promising template for the fabrication of novel nanomaterials and nanostructures. Despite being an ideal source, the Escherichia coli -derived TMV nanorod is suffering from tenuous assembly capability and stability. Inspired by the disulfide bond widely employed in biosystems, here we rationally introduce a cysteine into TMV coat protein (TMV-CP) to enable disulfide bond formation between adjacent subunits, thereby radically altering the behaviors of original noncovalent assembling system of wild type TMV-CP. The dramatically enhanced self-assembly capability and stability of the engineered TMV nanorods are observed and the essential roles of disulfide bonds are verified, illustrating a promising strategy to obtain desired genetic-modified nanorods that are inaccessible in plants. We expect this work will benefit the development of TMV-based nanotechnology and encourage the utilization of disulfide bonds in other biomacromolecules for improved properties as nanoscaffolds.