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Synthesis and characterization of Se-adenosyl-L-selenohomocysteine selenoxide.

ABSTRACT: Selenium is an essential micronutrient in humans due to the important roles of the selenocysteine-containing selenoproteins. Organoselenium metabolites are generally found to be substrates for the biochemical pathways of their sulfur analogs, and the redox chemistry of selenomethionine and some other metabolites have been previously reported. We now report the first synthesis and characterization of Se-adenosylselenohomocysteine selenoxide (SeAHO) prepared via hydrogen peroxide oxidation of Se-adenosylselenohomocysteine (SeAH). The selenoxide SeAHO, in contrast to its corresponding sulfoxide S-adenosylhomocysteine (SAHO), can form hydrate, has an electrostatic interaction between the ?-amino acid moiety and the highly polar selenoxide functional group, and readily oxidizes glutathione (GSH) and cysteine thiols.

SUBMITTER: Duclos RI

PROVIDER: S-EPMC4437643 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Synthesis and characterization of Se-adenosyl-L-selenohomocysteine selenoxide.

Duclos Richard I RI Cleary Dillon C DC Catcott Kalli C KC Zhou Zhaohui Sunny ZS

Journal of sulphur chemistry 20150401 2

Selenium is an essential micronutrient in humans due to the important roles of the selenocysteine-containing selenoproteins. Organoselenium metabolites are generally found to be substrates for the biochemical pathways of their sulfur analogs, and the redox chemistry of selenomethionine and some other metabolites have been previously reported. We now report the first synthesis and characterization of Se-adenosylselenohomocysteine selenoxide (SeAHO) prepared via hydrogen peroxide oxidation ...[more]

PMID: 26005494

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