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Volume 5
Toxicology: Open Access
Toxicology Congress 2019
May 06-07, 2019
May 06-07, 2019 Tokyo, Japan
20
th
World Congress on
Toxicology and Pharmacology
Toxicol Open Access 2019, Volume 5
DOI: 10.4172/2476-2067-C1-009
Arsenic trioxide induces structural perturbation of hen egg white lysozyme towards oligomers
formation
Satish Kumar and Neelakant Varma
Gujarat Forensic Sciences University, India
A
rsenic trioxide is one of the most common metallic pollutants entering the food chain both by human activities and nature.
Its introduction to living organism and accumulation is known to manifest several metabolic and hormonal disorders;
however its role in protein misfolding and aggregation followed by neurodegenerative disorders is not fully elucidated. In
the present study by employing several biophysical techniques, we reveal the aggregation mechanism of Hen Egg White
Lysozyme (HEWL) in presence of Arsenic Trioxide (As
2
O
3
) at physiological condition and characterized the aggregates. Our
ThT fluorescence and scattering data shows that As
2
O
3
promote the
in vitro
aggregation of HEWL in concentration dependent
manner. Early phase of aggregation was observed to be induced by exposure of hydrophobic surfaces which later reorganized to
promote further self-association leading to β sheet structure which was evident by CD spectroscopy. Presence of lower ordered
oligomers after two days and higher ordered oligomers along with amorphous aggregates, as evident by AFM after week long
incubation, indicate that As
2
O
3
drives the self-assembly of lysozyme towards oligomers form. It is now been believed that not
the mature fibrils but the transiently formed oligomers are the real culprit of several neurodegenerative disorders. Though we
did not observed any mature fibrils in present study, presence of oligomers of Rh ~62 nm and ~222 nm indicate that heavy
metal promotes small and medium sized oligomers which could be potential toxic species of arsenic mediated toxicity. With
the fact that several environmental pollutants including heavy metals are continually entering the living organism resulting
into various chronic disorders, present study provides a new insight about arsenic driven protein aggregation and toxicity
associated with that.
satish.kumar@gfsu.edu.in