@article{mbs:/content/journal/jmm/10.1099/00222615-48-2-139, author = "BACON, DAVID J. and JOHNSON, WENDY M. and RODGERS, FRANK G.", title = "Identification and characterisation of a cytotoxic porin-lipopolysaccharide complex from Campylobacter jejuni", journal= "Journal of Medical Microbiology", year = "1999", volume = "48", number = "2", pages = "139-148", doi = "https://doi.org/10.1099/00222615-48-2-139", url = "https://www.microbiologyresearch.org/content/journal/jmm/10.1099/00222615-48-2-139", publisher = "Microbiology Society", issn = "1473-5644", type = "Journal Article", abstract = "A clinical isolate of Campylobacter jejuni, previously found to produce a toxin active in cell culture assays, was used for identification and characterisation of a cytotoxic porin-lipopolysaccharide (LPS) complex. This cytotoxic complex was isolated by high-performance liquid chromatography of crude concentrated culture supernate and DEAE-anion exchange chromatography. The complex had a toxic activity of 20.1 tissue culture dose50 (TCD50)/μg of protein for HEp-2 cells, 7.49 TCD50/μg of protein for HeLa cells and 1.87 TCD50/μg of protein for Chinese hamster ovary cells. Analysis by SDS-PAGE revealed a single protein band of 45 kDa and a high mol. wt carbohydrate moiety. The complex gave a positive result in the Limulus amoebocyte lysate test, indicating that the co-purifying carbohydrate was LPS, and had specificity for the lectins Galanthus nivalis agglutinin, Maackia amurensis agglutinin and Datura stramonium agglutinin. The cytotoxic activity associated with the complex was heat-labile at 70°C, resistant to inactivation with trypsin and retained activity after treatment with sodium metaperiodate and the glycosidases neuraminidase and N-glycosidase F. Sequencing of the N-terminus of the protein component of the complex revealed 97% homology with the major outer-membrane porin protein from C. jejuni. The cytotoxic activity of the complex was neutralised by a polyclonal, homologous antiserum, which reacted on Western blot with the 45-kDa protein, but not by polyclonal antisera raised against a number of other bacterial toxins.", }