A method for detecting Shiga toxin and Shiga-like toxin-I in pure and mixed culture

S. Ashkenazi, T. G. Cleary*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

21 Scopus citations

Abstract

Shiga toxin and Shiga-like toxins (SLTs, syn. Verotoxins) are currently detected by tissue culture assays that are expensive, time-consuming and require specialised facilities and experienced personnel. We have developed a rapid method to detect Shiga toxin and SLT-I (Verotoxin 1) based on their binding to globotriosyl ceramide (Gb3). Bound toxin was then detected by an enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies. The direct detection of cytotoxins from pure culture plates and from a mixed bacterial culture was studied. Using polymyxin extraction (0.1 g/L, 30 min, 37°C) and Gb3-based ELISA we detected toxin from reference strains Shigella dysenteriae 1 strain 60R (Shiga toxin) and Escherichia coli O26:H11 strain H30 (SLT-I), and from clinical isolates of E. coli O157:H7 and O26:H11 (both SLT-I) from 11 patients with diarrhoea, haemorrhagic colitis or haemolytic uraemic syndrome. Toxin production by these strains was confirmed by a radiolabelled HeLa cell assay and the structural genes were detected by DNA hybridisation. The Gb3-based ELISA could detect SLT-I in extracts of a mixed culture even when the toxin-positive strains represented only 1% of the mixture. No cross-reactivity was found with bacteria that produce other cytotoxins, such as other E. coli and Shigella, Salmonella, Aeromonas and Campylobacter spp.

Original languageEnglish
Pages (from-to)255-261
Number of pages7
JournalJournal of Medical Microbiology
Volume32
Issue number4
DOIs
StatePublished - 1990
Externally publishedYes

Funding

FundersFunder number
Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentP01HD013021

    Fingerprint

    Dive into the research topics of 'A method for detecting Shiga toxin and Shiga-like toxin-I in pure and mixed culture'. Together they form a unique fingerprint.

    Cite this