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Polymers and Self Assembly: From Biology to Nanomaterials Poster Session II
5-POS
Board 5
Nano-encapsulated Assemblies Derived from a Non-enveloped Virus Capsid Protein for
Targeted Delivery
Saumya Bajaj
, Manidipa Banerjee.
Indian Institute of Technology Delhi, New Delhi, India.
Viruses exemplify uniform self-assembly - multiple copies of single (or few) coat proteins
assemble spontaneously in a precisely regulated manner into highly regular and symmetrical
capsid shells. The viral genome is protected within these nano-sized containers. Viruses are
stable enough to protect the genomic content, and yet pliable enough to release this payload into
host cells. This makes viruses fine candidates for development of biomaterials for drug delivery;
the engineering of viral capsid proteins and encapsulation of functional cargo in them is one of
the subjects of current research in nanobiotechnology. The aim of this work is to explore the
capsid protein of a non-enveloped insect nodavirus, Flock House Virus (FHV), as a building
block for nano-encapsulated structures for targeted delivery to cancer cells. FHV is a structurally
simple virus, being made up of 180 copies of a single capsid protein alpha that presumably
contains all the information needed for higher-order assembly. We have expressed alpha in a
heterologous (bacterial) expression system and shown its calcium-templated assembly into
morphologically diverse particles, the structures of which we are analyzing through electron
microscopy and single-particle reconstruction. To the best of our knowledge, this is the first
report utilizing
E. coli
to produce FHV particles. Considering that insect cell-produced FHV
VLPs have been shown to be carriers of transposable elements, an expression system where
in
vitro
self-assembly is encouraged will be of considerable benefit for its biomedical applications.
We have genetically engineered tumor-homing peptide Lyp-1 into a surface exposed loop of
alpha, thus generating
in vitro
assembled, nano-encapsulated particles with tumor-binding
capability. We are using these viral nanoparticles for targeting cancer cells. Thus, we have
developed a candidate functional biomaterial for targeted drug delivery.