[Protein damage after treatment with ozone of protoplasts and isolated E. coli membranes]

The features of ozone-induced damage of E. coli plasma membrane proteins are investigated. A conclusion is made that protein fluorescence quenching is connected with modification of amino acid residues in the vicinity of tryptophane residues. Such modification may be a consequence of reaction with either ozone itself or products of its interaction with membrane lipids and/or proteins. The suggestion of Goldstein and McDonagh that ozone has a predilection for more hydrophilical membrane domains is confirmed. The data obtained are in agreement with a supposition about the leading role of proteins in deleterious action of ozone on cells.