Title:
Evolution of Co-factor driven Dynamic Peptide Libraries

Abstract:
Proteins are an indispensible component of the modern biological
metabolic machinery. A key part of understanding and emulating their
function is to converge them into their minimalistic components.
Considering the complexity that has evolved over billions of years this
seems to be a non-trivial task. However, if an approach is to be
formulated, for in vitro evolution that could potentially rival in natura
evolution a co-factor driven formation of peptidic materials is to be
sought. Recently, Pappas et al.1 showed that library of dipeptides can be
used for dynamic evolution of nano materials. In this work we modified this
approach to amplify peptide sequences which assemble selectively on binding
with specialized co-factors. The co-factors that we chose for this work
were porphyrin derivatives and highly relevant biomolecules such as RNA,
DNA and ATP. Among porphyrins, we chose specifically three derivatives,
Hemin (natural) TMPyP, Fe-TMPyP (synthetic). Rationale for selec!
ting thes
e derivatives was to eventually create functional peptidic assemblies that
could partake in various photo-physical phenomena, endogenous to the
porphyrin systems.2 We selected seven dipeptides for our dynamic library,
allowing each set to evolve in solution with thermolysin and respective
Co-factor. The results of evolving libraries and their consequences would
be presented in the talk.

This approach has been developed as an in vitro auxiliary driven library
which can further be used for finding binders of more complex molecules
such as RNA and DNA expanding the signaficance of the approach into
possible pre-biotic investigation.

References

1) C.G. Pappas, R. Shafi, I.R. Sasselli, H. Siccardi, T. Wang, V. Narang,
R. Abzalimov, N. Wijerathne, R.V. Ulijn, Nat. Nanotechnol., 2016, 11,
960-967.

2) K. Kalyanasundaram, M. N-Spallart, J. Phys. Chem., 1982, 86, 5163-5169.