been found to be very effective for the removal of a wide range of toxic metals from the environment as
compared to conventional methods. Nanoparticles enhancing microbial activity to remove toxic
pollutants is called “nanobioremediation.” Nano-based technologies not only reduce the costs of
cleaning up contaminated sites at a large scale, but also reduce the process time as well.
“Bionanotechnology” or “nanotechnology through biotechnology” is the bio-fabrication of nano-objects
or bifunctional macromolecules used as tools to construct or manipulate nano-objects. Wide
physiological diversity, small size, genetic manipulability and controlled culturability make microbial
cells ideal producers of nanostructures ranging from natural products, such as polymers and
magnetosomes, to engineered proteins or protein constructs, such as virus-like proteins (VLP) and
tailored metal particles [147]. Deinococcus radiodurans, a radioactive-resistant organism, has the ability
to withstand radiation well beyond the naturally occurring levels, thus its application in radioactive waste
clean-up initiatives funded by US Department of Energy (DOE) [130,148]. Metal chelating polymers
require toxic solvents for their synthesis and ultrafiltration for their separation, and this can be solved by
developing metal binding materials that can be recovered by changing the environment surround them
like pH, temperature etc. One such material is nanoscale modified biopolymers, which are manufactured
by genetic and protein engineering of microorganisms, and their size can be controlled at the molecular
level [149]. This innovative technique would be a promising tool to address the escalating problem of
heavy metal as well as organic contaminants in the environment