Superoxide anion chemical properties

NOS products of neurons, epithelial cells and other cells in the lung have both bronchodilator and inflammatory properties (Gaston etal., 1994b) the specific nature of this bioactivity depends on the chemical characteristics of the functional products in the specific microenvironment under consideration. For example, NO is capable of complexing with and affecting the activity of a variety of metalloproteins and enzymes, such as guanylyl cyclase and ribonucleotide reductase (Nathan, 1992 Stamler et al., 1992). NO can also complex with superoxide anion to form peroxynitrite, which has a cytotoxic immune effector role (Radi etal., 1991 Stamler etal., 1992). Furthermore, NO can form iron nitrosyl complexes, which are the putative intracellular macrophage products of iNOS responsible for lysis of intracellular parasites (Hibbs... 

In the preceding chapters — with the exception of the discussion of different flavoproteins — no such discussion was started regarding the specificity of the superoxide anion as the sole substrate for erythrocuprein. In this context let us recall some basic principles of the chemical and physical properties of oxygen (for extensive reviews see Refs. (172— 178 a)). 

Extensive reviews of the chemical properties of the superoxide anion are in Sawyer and Valentine 308) and in Sawyer 311). 

Oxygen takes up one electron to form the superoxide radical anion (O2). This anion radical is a reducing agent with chemical properties dependent on pH, according to the equilibrium ... 

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