<p>S-nitrosylation, the prototypic mechanism of redox-based signal transduction, involves the covalent attachment of a nitrogen monoxide group to a Cys-thiol side chain. S-nitrosylation of proteins has been demonstrated to affect a broad range of functional parameters including enzymatic activity, subcellular localization, protein-protein interactions and protein stability. The primary focus of my dissertation was to solve a problem of great importance in the field of S-nitrosylation, which is, to identify denitrosylase(s) i.e., enzymes that remove NO groups from S-nitrosothiols. Recent progress in elucidating the cellular regulation of S-nitrosylation has led to the identification of two physiologically relevant denitrosylating activities that remove the NO group from S-nitrosylated substrates. Thioredoxin/thioredoxin reductase (Trx system) functions as an NADPH-dependent denitrosylase across a broad range of S-nitrosylated proteins (SNO-proteins). S-nitroso-glutathione reductase (GSNOR), which is highly conserved across phylogeny, metabolizes GSNO utilizing NADH as a reducing coenzyme, thereby shifting equilibria between GSNO and SNO-proteins. This dissertation describes the discovery of two novel denitrosylases: one from yeast and the other from mammals. Using technique of column chromatography we have purified these novel denitrosylases to homogeneity and have demonstrated a principal contribution of these enzymes towards S-nitrosothiol metabolism.</p> / Dissertation
| Identifer | oai:union.ndltd.org:DUKE/oai:dukespace.lib.duke.edu:10161/6165 |
| Date | January 2012 |
| Creators | Anand, Puneet |
| Contributors | Stamler, Jonathan S, Kreuzer, Kenneth N |
| Source Sets | Duke University |
| Detected Language | English |
| Type | Dissertation |
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