Open AccessEffect of O‐antigenic polysaccharide of Escherichia coli on endotoxin neutralizing activity of lysozyme
Author(s) -
Liang Aihua,
Sugawara Naoto,
Ohno Naohito,
Adachi Yoshiyuki,
Yadomae Toshiro
Publication year - 1998
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.1998.tb01152.x
Subject(s) - lysozyme , microbiology and biotechnology , biology , escherichia coli , polysaccharide , antigen , enterobacteriaceae , bacteria , muramidase , biochemistry , immunology , gene , genetics
Endotoxemia is considered to be associated with the high mortality of Gram‐negative septic patients. Increasing evidence shows that β‐lactam antibiotics have a propensity to induce endotoxin release from the bacterial outer membrane while killing bacteria. We have recently found that egg white lysozyme (EW‐LZM) shows strong inhibition of β‐lactam induced bacteriolysis and lipopolysaccharide (LPS) release from Escherichia coli O111, resulting in reduction of the LPS‐initiated inflammatory response. In this study, we compared the effect of EW‐LZM on E. coli J5, which possesses rough‐type LPS (RaLPS), in order to demonstrate the effect of O‐antigenic polysaccharide on endotoxin neutralizing activity of EW‐LZM and on inhibition of β‐lactam induced lysis by LZM. Both of the β‐lactam induced bacterial lysis and subsequent LPS release were almost completely inhibited by EW‐LZM. The effect was more potent than that of wild‐type LPS as assessed by released LPS concentration and LPS induced cytokine syntheses. In addition, EW‐LZM was effective against lethal infection of E. coli J5 in cyclophosphamide induced leukopenic mice. These facts strongly suggested that O‐antigenic polysaccharide negatively modulates LPS neutralizing activity of EW‐LZM.