Release of membrane vesicles containing endotoxic lipopolysaccharide in Escherichia coli O157:H7 clinical isolates |
| |
Authors: | Meno Y Fujimoto S Horikawa K Yoshida S |
| |
Institution: | Faculty of Health and Welfare, Seinan Jogakuin University Kitakyushu, Fukuoka, Japan. Yuko.Meno@ma6.seikyou.ne.jp |
| |
Abstract: | Membrane vesicles released by E. coli O157:H7 strains were investigated by immuno-electron microscopy using anti-O157 antibody. Anti-O157 antibody enhanced the negative-staining of vesicles and we found numerous small vesicles clearly formed around bacterial cells. An immunogold-electron microscopic examination confirmed that lipopolysaccharide (LPS) including the O-side chain is present on the surface of the vesicles. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of the purified vesicles showed that the vesicles contained LPS consisting of a lipid-A and an O polysaccharide. In addition, the endotoxic activity of the vesicle was confirmed by a limulus test. These results suggest that the vesicles may play an important role in the pathogenesis of Escherichia coli O157:H7. |
| |
Keywords: | membrane vesicle endotoxin lipopolysaccharide escherichia coli O157:H7 electron microscopy |
本文献已被 PubMed 等数据库收录! |