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Selenols are resistant to irreversible modification by HNO
Christopher L Bianco1, Cathy D Moore1, Jon M Fukuto2
1Department of Chemistry, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA.
Free Radical Biology & Medicine
|July 18, 2016
Summary
Nitroxyl (HNO) targets selenols, forming reversible diselenide products. This suggests selenoproteins are resistant to irreversible oxidative damage, unlike thiol proteins, highlighting selenium
Area of Science:
- Chemical biology of nitrogen oxides
- Redox signaling and cellular defense mechanisms
Background:
- Nitric oxide (NO) and nitroxyl (HNO) are endogenous signaling molecules.
- HNO is investigated for cardiovascular disease therapeutics.
- HNO targets hemes, heme proteins, and thiols.
Purpose of the Study:
- To investigate if selenols and selenoproteins are targets of nitroxyl (HNO).
- To characterize the reaction products of HNO with selenols.
- To compare the reactivity of HNO with selenols versus thiols.
Main Methods:
- Chemical characterization of reactions between HNO and selenols.
- Analysis of reaction products and reversibility.
Main Results:
- Selenols are indeed targeted by nitroxyl (HNO).
- HNO reactions with selenols yield diselenide products.
- These diselenide products are readily reverted to free selenols.
Conclusions:
- Selenoproteins exhibit resistance to irreversible oxidative modification by HNO.
- This resistance is distinct from the reaction of HNO with thiol proteins.
- Nature may utilize selenium over sulfur for enhanced resistance in biological systems.
Keywords:
BenzeneselenolCysteineDiselenideDisulfideN-hydroxyselenenamideN-hydroxysulfenamideNitroxylSeleninamideSeleniumSelenocysteineSelenoenzymesSelenolSulfinamideThiolMore Related Videos
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