Cloning, expression and analysis of the olfactory glutathione S-transferases in coho salmon.
Article Details
- CitationCopy to clipboard
Espinoza HM, Shireman LM, McClain V, Atkins W, Gallagher EP
Cloning, expression and analysis of the olfactory glutathione S-transferases in coho salmon.
Biochem Pharmacol. 2013 Mar 15;85(6):839-48. doi: 10.1016/j.bcp.2012.11.018. Epub 2012 Dec 19.
- PubMed ID
- 23261526 [ View in PubMed]
- Abstract
The glutathione S-transferases (GSTs) provide cellular protection by detoxifying xenobiotics, maintaining redox status, and modulating secondary messengers, all of which are critical to maintaining olfaction in salmonids. Here, we characterized the major coho salmon olfactory GSTs (OlfGSTs), namely omega, pi, and rho subclasses. OlfGST omega contained an open reading frame of 720bp and encoded a protein of 239 amino acids. OlfGST pi and OlfGST rho contained open reading frames of 627 and 681nt, respectively, and encoded proteins of 208 and 226 amino acids. Whole-protein mass spectrometry yielded molecular weights of 29,950, 23,354, and 26,655Da, respectively, for the GST omega, pi, and rho subunits. Homology modeling using four protein-structure prediction algorithms suggest that the active sites in all three OlfGST isoforms resembled counterparts in other species. The olfactory GSTs conjugated prototypical GST substrates, but only OlfGST rho catalyzed the demethylation of the pesticide methyl parathion. OlfGST pi and rho exhibited thiol oxidoreductase activity toward 2-hydroxyethyl disulfide (2-HEDS) and conjugated 4-hydroxynonenal (HNE), a toxic aldehyde with neurodegenerative properties. The kinetic parameters for OlfGST pi conjugation of HNE were K(M)=0.16 +/- 0.06mM and V(max)=0.5 +/- 0.1mumolmin(-)(1)mg(-)(1), whereas OlfGST rho was more efficient at catalyzing HNE conjugation (K(M)=0.022 +/- 0.008 mM and V(max)=0.47 +/- 0.05mumolmin(-)(1)mg(-)(1)). Our findings indicate that the peripheral olfactory system of coho expresses GST isoforms that detoxify certain electrophiles and pesticides and that help maintain redox status and signal transduction.
DrugBank Data that Cites this Article
- Drug Enzymes
Drug Enzyme Kind Organism Pharmacological Action Actions 2-Hydroxyethyl Disulfide Glutathione S-transferase A1 Protein Humans UnknownSubstrateDetails