title: The potential physiological implications of polygalacturonic acid-mediated production of superoxide.
abstract: PGA/OGA/PF represent apoplastic signaling molecules implicated in the control of gene expression and the activity of enzymes involved in defense regulation. However, the underlying mechanisms behind such processes are lacking. Here we unequivocally show using EPR spectroscopy with DEPMPO spin-trap capable of differentiating between •OH and •O(2)(-) that PGA and PF can produce •O(2)(-) by transforming •OH. The potential physiological implications of this unique property are discussed. We propose that PGA/OGA/PF could represent the initiators of redox signaling cascades in stress response, with H(2)O(2) being a downstream secondary messenger.
authors.affiliation: Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia. ivan@cms.bg.ac.rs
authors.forename: Ivan
authors.initials: I
authors.lastname: Spasojević
authors.forename: Jelena Bogdanović
authors.initials: JB
authors.lastname: Pristov
mesh_terms: D004578:Electron Spin Resonance Spectroscopy; D004798:Enzymes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D010084:Oxidation-Reduction; D010368:Pectins / Q000378:metabolism*; D010944:Plants / Q000235:genetics / Q000378:metabolism; D019097:Spin Trapping; D013481:Superoxides / Q000378:metabolism*
chemical_list: D004798:Enzymes; D013481:Superoxides; D010368:Pectins; C003181:polygalacturonic acid