Back to Search
Start Over
Tyrosine nitration affects thymidylate synthase properties.
- Source :
-
Organic & biomolecular chemistry [Org Biomol Chem] 2012 Jan 14; Vol. 10 (2), pp. 323-31. Date of Electronic Publication: 2011 Nov 09. - Publication Year :
- 2012
-
Abstract
- Highly purified preparations of thymidylate synthase, isolated from calf thymus, and L1210 parental and FdUrd-resistant cells, were found to be nitrated, as indicated by a specific reaction with anti-nitro-tyrosine antibodies, suggesting this modification to appear endogenously in normal and tumor tissues. Each human, mouse and Ceanorhabditis elegans recombinant TS preparation, incubated in vitro in the presence of NaHCO(3), NaNO(2) and H(2)O(2) at pH 7.5, underwent tyrosine nitration, leading to a V(max)(app) 2-fold lower following nitration of 1 (with human or C. elegans TS) or 2 (with mouse TS) tyrosine residues per monomer. Enzyme interactions with dUMP, meTHF or 5-fluoro-dUMP were not distinctly influenced. Nitration under the same conditions of model tripeptides of a general formula H(2)N-Gly-X-Gly-COOH (X = Phe, Tyr, Trp, Lys, Arg, His, Ser, Thr, Cys, Gly), monitored by NMR spectroscopy, showed formation of nitro-species only for H-Gly-Tyr-Gly-OH and H-Gly-Phe-Gly-OH peptides, the chemical shifts for nitrated H-Gly-Tyr-Gly-OH peptide being in a very good agreement with the strongest peak found in (15)N-(1)H HMBC spectrum of nitrated protein. MS analysis of nitrated human and C. elegans proteins revealed several thymidylate synthase-derived peptides containing nitro-tyrosine (at positions 33, 65, 135, 213, 230, 258 and 301 in the human enzyme) and oxidized cysteine (human protein Cys(210), with catalytically critical Cys(195) remaining apparently unmodified) residues.
- Subjects :
- Animals
Caenorhabditis elegans enzymology
Cattle
Cell Line, Tumor
Humans
Mice
Recombinant Proteins chemistry
Recombinant Proteins isolation & purification
Recombinant Proteins metabolism
Thymidylate Synthase chemistry
Thymidylate Synthase isolation & purification
Thymus Gland enzymology
Tyrosine chemistry
Thymidylate Synthase metabolism
Tyrosine metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1477-0539
- Volume :
- 10
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Organic & biomolecular chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 22072032
- Full Text :
- https://doi.org/10.1039/c1ob06360j