Many enzymes exploit the oxidation states of metals to perform redox cycling
. Fundamental biological processes in which metalloproteins participate include electron storage and transfer, dioxygen binding, storage and activation, and substrate transport, catalysis and activation.
Redox-active metals, such as iron, copper and chromium, undergo redox cycling
whereas redox-inactive metals, such as lead, cadmium, mercury and others deplete cells' major antioxidants, particularly thiol-containing antioxidants and enzymes.
Oxygen radical formation by redox cycling
is a critical part of the toxic effects of various compounds when the cell oxidant-antioxidant balance is disrupted.
The water-soluble copper porphyrinate, copper (II) porphyrinate (CuTPPs = [5,10,15,20- tetrakis(N-methylpyridyl-4)porhinato]copper(II) tetratosylate)), was previously examined by UV-Vis and electron paramagnetic (EPR) spectroscopy for its ability to engage in a number of reactions involving either axial ligation to the copper or possible redox cycling
, with ligands and potential redox partners such as nitrite, imidazole, dithionite, 2,2'-azino-bis(3- ethylbenzthiazoline-6-sulphonic acid) (ABTS) and guaiacol .
As to circumvent the complications associated with the dimerization of V+ and electro deposition of V+ and/ or V, 9: 1(v/v) DMF/H2O mixed solvent has been used, it might become useful for the advance study of applications of non-alkyl group substituted and long alkyl chain substituted viologens and may provide a new avenue to study how these viologens trigger redox cycling
Zhu, "Hydroxyl radical generation mechanism during the redox cycling
process of 1,4-naphthoquinone," Environmental Science & Technology, vol.
The topics include the molecular regulation of selenocysteine incorporation into proteins in eukaryotes, a historical view of redox cycling
and the toxicity of selenium compounds, forms of selenium in cancer prevention, multifaceted and intriguing effects of selenium and selenoproteins on glucose metabolism and diabetes, and the functionality and disease risk of genetic polymorphisms in selenoprotein genes.
As an intermediate of glucose metabolism in [beta] cells, pyruvate plays an important role in redox cycling
between NADH and NADPH [41, 45, 46].