Project description:Shiga toxin type 2 (Stx2) is the main virulence factor produced by Stx-producing Escherichia coli (STEC) responsible for hemorrhagic colitis and the life-threatening sequela hemolytic uremic syndrome.
Project description:Intestinal tissue responses to protein synthesis inhibition by Shiga toxin are complex. Organoid models allow for an unprecedented examination of human tissue responses to a deadly Shiga toxin.
Project description:Enterohaemorrhagic E. coli is significant human pathogen that causes disease ranging from haemorrhagic colitis to haemolytic uremic syndrome. The later can lead to potentially fatal renal failure and is caused by the release of Shiga toxins that are encoded within lambdoid bacteriophages. The toxins are encoded within the late transcript of the phage and are regulated by anti-termination of the PR’ late promoter during lytic induction of the phage. During lysogeny, the late transcript is prematurely terminated at tR’ immediately downstream of PR’, generating a short RNA that is a by-product of anti-termination regulation. We demonstrate that this short transcript binds the small RNA chaperone Hfq, and is processed into a stable 74 nt regulatory small RNA that we have termed, StxS. StxS activates expression of the general stress response sigma factor, RpoS, through direct interactions with an activating seed sequence within the 5’ UTR. StxS represses expression of Shiga toxin 1 and activation of RpoS promotes high cell density growth under nutrient limiting conditions. Many phages utilise anti-termination to regulate the lytic/lysogenic switch and our results demonstrate that short RNAs generated as a by-product of this regulation can acquire regulatory small RNA features and modulate host fitness.
2020-09-16 | GSE143631 | GEO
Project description:Comparative Genomics of Shiga toxin-producing Escherichia coli (STEC) strains from pediatric patients with and without haemolytic uremic syndrome (HUS), 2000-2016, Finland
