| Alice Chanakira |
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| Present Work and Research |
|
My project
involved the study of the kinetics and
mechanism of the oxidation of the
biologically active organosulfur compound
Cysteamine with acidic iodate and molecular
iodine.
Cysteamine is a very important biological
molecule. Medically known as Cystagon, it
can be used as oral therapy for prevention
of hypothyroidism and enhances growth in
patients with nephropathic cystinosis, a
lysosomal storage disorder which was long
considered primarily a renal disease, but
it's now recognized as systemic disorder
which eventually effects many organ systems
in children. Cysteamine is also an excellent
scavenger of
.OH
and HOCl; it also reacts with H2O2,
but reaction with O2-.
has not yet been ascertained. It has been
shown that cysteamine and its metabolite
hypotaurine are far more likely to act as
antioxidants in vivo than is taurine,
provided that they are present in sufficient
concentration at sites of oxidant
generation. Hypotaurine differs from taurine only in the oxidation state of the sulfur center and the resulting change in the acidity of the molecule. Cysteamine is oxidized to the sulfinic derivative (hypotaurine) only in the presence of cofactor-like compounds such as sulfide, methylene blue and hydroxyalamine. Most metabolic pathways give hypotaurine as a precursor to taurine. It was observed that in the presence of acidic iodate and iodine, the reaction dynamics are complex and display clock behavior, transient iodine production and even oligooscillatory production of iodine depending upon initial conditions. The final oxidation product was the cysteamine dimer, cystamine. Another on-going project that I am involved in is the study of chemical systems generating chaotic dynamics, in particular chemical oscillations and traveling waves generated by the chlorite oxidation of Thiourea. This is an ongoing project that we hope will give us further insight into temporal and spatiotemporal chaos of organosulfur compounds. |