chemistry-2018-keynote

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E u r o S c i C o n C o n f e r e n c e o n
Chemistry
2018
Journal of Organic & Inorganic Chemistry
ISSN 2472-1123
F e b r u a r y 1 9 - 2 0 , 2 0 1 8
P a r i s , F r a n c e
Chemistry 2018
Page 11
Protein capsids formnanometer-scale, closed shell structures via self-assembly
that can host various cargomolecules in their hollow interiors.Thesemolecular
containers can be useful for applications such as drug delivery, nanoreactors and
materials synthesis. These applications often require the encapsulation of cargo
molecules followed by their eventual release from the capsid. However, general
methods for loading and unloading cargomolecules are lacking. My research aims
to endow protein capsids with the ability to encapsulate different cargo molecules
and to develop non-denaturing cargo release mechanisms. The capsids formed
by bacterial lumazine synthases (LS’s) are attractive structures for engineering
molecular encapsulation systems. Using DNA mutagenesis and covalent protein
modification methods, LS capsids and potential guests were convergently
engineered to generate interactions that are localized to the capsid interior and
that can potentially be modulated by changing the solution conditions. Structural
and functional characterizations of the resulting complexes are carried out
using biochemical and biophysical techniques. Using a charge complementarity
strategy, engineered LS capsids were loaded with RNA cargoes during bacterial
production. Similarly, a natural LS capsid was loaded with a protein bearing a
peptide tag derived from its native guest. The protein cargo was released from the
capsid by a mild change in the buffer conditions. Lastly, small-molecule cargo was
loaded into an intact engineered LS capsid using a covalent capture strategy. The
bond linking the cargo to the capsid can be broken by reducing agents, allowing for
triggered release of a toxic molecule in cells. These strategies for reversible guest
encapsulation extend the functional versatility of the LS capsid as a scaffold for
bio-nanotechnology. The ability to control both cargo loading, and release should
be particularly useful for the development of new drug delivery systems.
Biography
Kenneth J Woycechowsky obtained his BS in Chemistry from
Penn State University and a PhD in Biochemistry from the Uni-
versity of Wisconsin–Madison. Following Postdoctoral studies
at ETH Zurich, he became an Assistant Professor in the Depart-
ment of Chemistry at the University of Utah. In 2014, he moved
to China, where he is currently a Professor in the School of
Pharmaceutical Science and Technology at Tianjin University.
He has expertise in the assembly, folding, function, and engi-
neering of proteins. His work on protein capsid assembly and
the engineering of protein capsids to construct novel molecular
encapsulation systems helps lay the ground work for next-gen-
eration nanoreactors and drug delivery systems.
Protein capsids as molecular containers:
cargo loading and controlled release
Kenneth J Woycechowsky
Tianjin University, China
Kenneth J Woycechowsky, J Org Inorg Chem 2018, Volume: 4
DOI: 10.21767/2472-1123-C1-001