Publication Date:
1988-11-11
Description:
Despite its potential toxicity, H2O2 is used as an extracellular oxidant by Stronglylocentrotus purpuratus eggs to cross-link their fertilization envelopes. These eggs contain 5 mM 1-methyl-N alpha,N alpha-dimethyl-4-mercaptohistidine (ovothiol C), which reacts with H2O2. In consuming H2O2 and being reduced by glutathione, ovothiol acts as a glutathione peroxidase and replaces the function of the enzyme in eggs. The ovothiol system is more effective than egg catalase in destroying H2O2 at concentrations produced during fertilization and constitutes a principal mechanism for preventing oxidative damage at fertilization.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Turner, E -- Hager, L J -- Shapiro, B M -- GM23910/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1988 Nov 11;242(4880):939-41.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Washington, Seattle 98195.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/3187533" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acids, Sulfur/*metabolism
;
Animals
;
Catalase/metabolism
;
Disulfides/metabolism
;
Female
;
Fertilization
;
Glutathione/metabolism
;
Glutathione Peroxidase/*metabolism
;
Kinetics
;
*Methylhistidines
;
NADP/metabolism
;
Ovum/*metabolism
;
Oxidation-Reduction
;
Sea Urchins
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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