STEC toxins Stx1 and Stx2

Contamination of water by pathogenic Escherichia coli represents a major public health problem, and most pathogenic E. coli strains isolated from water cause persistent diarrhea.

Some of these strains (enterohemorrhagic E. coli ) are able to produce toxins similar to those produced by Shigella and particularly aggressive for humans: the Stx-1 toxin (identical to the Shigella toxin) together with the Stx-2 toxin (60% similarity to the Shigella toxin).

Their spread (EHEC) is assuming particular importance, and this subgroup includes the E. coli O157:H7 strain responsible for some major waterborne epidemics. The causes were attributed to the inefficiency of the water purification treatment, during a particularly rainy period that had led to significant soil leaching, and to the presence of sources of environmental contamination (e.g. livestock and pastures) that had contributed to the pollution of the water supply source.

For hydrodiffusion methods, there is also keen interest in irrigation and sprouting water. Two distinct test kits are available: one for the specific detection of toxins, the other for the determination of E. coli O157:H7 responsible for toxin production.

*   Licenze di brevetto WO 00/28082, WO 01/34790, WO 01/77317, WO 02/24902, WO 01/34838  ** Patent for industrial invention no. 0001425753 of 09.11.2016