The chemistry of peroxynitrite, a biological toxin<a name=TOP1></a>

Abstract

Recebido em 22/8/97Oxyradicals play a role in several diseases. While for several decades the hydroxyl radical -produced via the Fenton reaction -has been considered the species that initiates oxyradical damage, new findings suggest that much of this damage can be ascribed to peroxynitrite, O=NOO -, formed from the reaction of the superoxide anion with nitrogen monoxide near activated macrophages. The rate constant for the reaction of this reaction has been investigated by flash photolysis and was found to be significantly higher than previously described in the literature, 1.9 x 10 10 M -1 s -1 . Studies of the isomerization to nitrate resulted in the discovery of a complex between peroxynitrite and its protonated form with a stability constant of 1 x 10 4 M -1 . Some of the harmful reaction of peroxynitrous acid have been ascribed to the hydroxyl radical as a product of homolysis of the O-O bond during the conversion to nitrate. Kinetics of the isomerization reaction as a function of pressure show that the activation volume is only +1.5+1.0 ml mol -1 , which is inconsistent with homolysis. Instead, an intermediate, possibly a distorted trans-isomer of O=NOOH could be responsible for the harmful reactions of peroxynitrite.

Effects of Atmosphere Composition and Liquid Type on Plasma-Generated Reactive Species in Biologically Relevant Solutions

“…The role of peroxynitrite for medicine, especially for the inactivation of microorganisms, is described in detail in the literature. 3,[16][17][18][19][20][21] The formation in plasma-treated liquids and the antibacterial effect by the use of plasma-generated peroxynitrite in these liquids is also known. 3,20,22 Only for the case of plasma treated NaCl solution, the pH value is in a range, where reaction 6 can take place.…”

Oxidative pathways in response to polyunsaturated aldehydes in the marine diatom Skeletonema marinoi (Bacillariophyceae)

“…Biochemical reactions involved in the generation of reactive oxygen (ROS) and nitrogen (RNS) species and the interplay between these two reactions. Modified from Koppenol (1998).…”

Time-resolved luminescence detection of peroxynitrite using a reactivity-based lanthanide probe

“…[1][2][3][4] In contrast, elevated levels of ONOO À can lead to signicant oxidative and nitrosative damage to lipids, proteins and DNA and has been implicated in several diseases including Alzheimer's, Huntington's, and Parkinson's disease. [5][6][7] Therefore, ONOO À has become a very important target for detection in a cellular environment. The ability to detect ONOO À selectively would facilitate a better understanding of its roles in cellular biology, disease diagnosis, and therapies based on redox signalling events (e.g.…”