@misc{10481/63038,
year = {2014},
month = {2},
url = {http://hdl.handle.net/10481/63038},
abstract = {Post-translational modifications (PTMs) mediated by nitric oxide (NO)-derived molecules have become a new area
of research, as they can modulate the function of target proteins. Proteomic data have shown that ascorbate peroxidase (APX) is one of the potential targets of PTMs mediated by NO-derived molecules. Using recombinant pea cytosolic APX, the impact of peroxynitrite (ONOO–) and S-nitrosoglutathione (GSNO), which are known to mediate protein
nitration and S-nitrosylation processes, respectively, was analysed. While peroxynitrite inhibits APX activity, GSNO
enhances its enzymatic activity. Mass spectrometric analysis of the nitrated APX enabled the determination that Tyr5
and Tyr235 were exclusively nitrated to 3-nitrotyrosine by peroxynitrite. Residue Cys32 was identified by the biotin
switch method as S-nitrosylated. The location of these residues on the structure of pea APX reveals that Tyr235 is
found at the bottom of the pocket where the haem group is enclosed, whereas Cys32 is at the ascorbate binding site.
Pea plants grown under saline (150mM NaCl) stress showed an enhancement of both APX activity and S-nitrosylated
APX, as well as an increase of H2O2, NO, and S-nitrosothiol (SNO) content that can justify the induction of the APX
activity. The results provide new insight into the molecular mechanism of the regulation of APX which can be both
inactivated by irreversible nitration and activated by reversible S-nitrosylation.},
organization = {Spanish Government},
organization = {ERDF from the Ministry of Science and Innovation 	
BIO2009-12003-C02-01
BIO2009-12003-C02-02
BIO2012-33904},
organization = {Junta de Andalucia
	
BIO286
BIO192},
organization = {CICT of Universidad de Jaen (UJA, MINECO, Junta de Andalucia, FEDER)},
keywords = {Ascorbate peroxidase},
keywords = {Nitration},
keywords = {Nitric oxide},
keywords = {S-Nitrosoglutathione},
keywords = {S-nitrosylation},
keywords = {Peroxynitrite},
keywords = {Reactive nitrogen species},
keywords = {Salinity stress},
title = {Dual regulation of cytosolic ascorbate peroxidase (APX) by tyrosine nitration and S-nitrosylation},
doi = {10.1093/jxb/ert396},
author = {Begará Morales, Juan Carlos and Sánchez Calvo, Beatriz and Chaki, Mounira and Valderrama, Raquel and Mata-Pérez, Capilla and López Jaramillo, Francisco Javier and Padilla, María N. and Carreras, Alfonso and Corpas Aguirre, Francisco Javier and Barroso, Juan B.},
}