Selenium-containing enzymes in mammals: Chemical perspectives

@article{Roy2005SeleniumcontainingEI,
  title={Selenium-containing enzymes in mammals: Chemical perspectives},
  author={Gouriprasanna Roy and Bani Kanta Sarma and Prasad P. Phadnis and Govindasamy Mugesh},
  journal={Journal of Chemical Sciences},
  year={2005},
  volume={117},
  pages={287-303}
}
The chemical and biochemical route to the synthesis of the 21st amino acid in living systems, selenocysteine, is described. The incorporation of this rare amino acid residue into proteins is described with emphasis on the role of monoselenophosphate as selenium source. The role of selenocysteine moiety in natural mammalian enzymes such as glutathione peroxidase (GPx), iodothyronine deiodinase (ID) and thioredoxin reductase (TrxR) is highlighted and the effect of other amino acid residues… 
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Selenocysteine (Sec), the 21st proteinogenic amino acid, is inserted co-translationally into number of natural proteins. It is coded by a dual function stop codon UGA (opal). It is a redox active…
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TLDR
In this chapter, some of the well-studied examples of selenoenzymes and their synthetic mimics are discussed and the role of Sec in iodothyronine deiodinases, which control the thyroid hormone levels, is also discussed.
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TLDR
This study has synthesized a series of amine or amide-based diselenides containing an additional amino group as glutathione peroxidase (GPx) mimetics that act as a catalytic triad model of the native GPx featuring two basic amino groups near the selenium centre.
Synthesis and antioxidant activity of peptide-based ebselen analogues.
TLDR
The PN-scavenging activity of the Phe-based peptide analogues was found to be comparable to that of the Val-based compounds, and the difference in the catalytic activity of dipeptide-based ebselen derivatives can be ascribed mainly to the change in the reactivity of these compounds toward GSH and peroxide.
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TLDR
The glutathione peroxidase (GPx) activities of some diaryl diselenides incorporating tertiary amino groups were studied and revealed that the simple 6-OMe groups play multiple roles in each of the catalytically active intermediates by introducing steric and electronic effects that are required for efficient catalysis.
Stable selones in glutathione-peroxidase-like catalytic cycle of selenonicotinamide derivative.
TLDR
Estimated reactivity parameters for the reaction of selenium species, according to the Dalziel kinetic model, towards GSH (ϕGSH) and H2O2 ( ϕH2O 2), indicated that the rate constant for the Reaction of NictSeSeNict with GSH is higher as compared to that with H2 O2, indicating that the activity is initiated by reduction.
Bioinorganic chemistry aspects of the inhibition of thyroid hormone biosynthesis by anti-hyperthyroid drugs
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TLDR
This review summarizes the most recent findings on the biochemistry of active selenium species in humans, and addresses the latest evidence on the link betweenselenium intake, selenoproteins functionality and beneficial health effects.
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References

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