VTEC screening to detect a prophage sequence reported in O157 subpopulations from human patients.

BURGÁN, J.; KRÜGER, A.; LUCCHESI, P.M.A.

Bostón

Simposio; 9th Trienniel International Symposium on Shiga Toxin Producing Escherichia Coli Infections; 2015

Certain VTEC are associated with severe human infections, while others seem to be restricted to cattle. Thereby, a distinct subpopulation might have evolved to be either more virulent or adapted to survive in the food chain. Verocytotoxins (VTs) are bacteriophage-encoded and their expression is associated with the lytic cycle. The region between gam and cII genes encodes factors that control lytic and lysogenic states of the phage and the expression of late genes, included vtx. Tozzoli et al. (2014) developed primers amplifying a DNA sequence internal to this region (cro-cI) specific for phage Φ8 and determined that this cro-cI sequence was more frequent in O157 strains from human disease than from bovine.