the toxicity of RIPs to cells and consequently to animals is highly variable and depends on their structure: in general, type 1 RIPs have a lower toxicity than type 2 RIPs
hemolytic-uremic syndrome is generally caused by Shiga toxin-producing Escherichia coli. Endothelial dysfunction mediated by Stx is a central aspect in hemolytic-uremic syndrome development. Inflammatory mediators such as bacterial lipopolysaccharide and polymorphonuclear neutrophils contribute to HUS pathophysiology by potentiating Stx effects, pathology, overview
infection with Shiga toxin-producing Escherichia coli is the most significant cause of hemolytic uremic syndrome in humans, the leading cause of acute renal failure in children
Corynebacterium diphtheriae secretes the diphtheria toxin, a virulence factor that can be lethal to the human organism at doses below 0.0001 mg/kg of body weight. During infections, the toxin binds to the cell membrane and subunit A will enter the cytoplasm and catalyze the ADP-ribosylation and inactivation of elongation factor 2 thus killing the eukaryotic cell by inhibiting ribosomal translocation
ricin induces the expression of unfolded protein response genes, the (protein kinase RNA-activated)-like endoplasmic reticulum kinase branch of the unfolded protein response, and activates the activating transcription factor 6 pathway of the unfolded protein response, but not the inositol-requiring protein 1 branch
ricin is highly toxic as it contains, in addition to the enzymatically active A chain, a second B chain that binds to galactose-containing surface molecules mediating endocytosis of the RIP
riproximin induces the (protein kinase RNA-activated)-like endoplasmic reticulum kinase branch of the unfolded protein response and activates the activating transcription factor 6 pathway of the unfolded protein response, but not the inositol-requiring protein 1 branch
saporin expression is toxic to tobacco protoplasts. Saporin toxicity undergoes signal sequence-specific regulation when the host cell is subjected to endoplasmic reticulum stress
Shiga toxins (Stx) expressed in the intestinal lumen during infection with Shiga-toxigenic Escherichia coli must translocate across the epithelium and enter the systemic circulation to cause systemic (pathological) effects, including hemolytic uremic syndrome. Even though Stxs are potent protein synthesis inhibitors, both isoforms Stx1 and Stx2 have been shown to upregulate interleukin-8 protein expression in intestinal epithelial cells via the ribotoxic stress response, a signal transduction event resulting from specific damage to the 28S rRNA that causes activation of host stress-activated protein kinases. Stx1 and Stx2 are also capable of inducing MAPK activation in vitro
volkensin induces the (protein kinase RNA-activated)-like endoplasmic reticulum kinase branch of the unfolded protein response, and activates the activating transcription factor 6 pathway of the unfolded protein response, but not the inositol-requiring protein 1 branch
BE27 displays antifungal activity against the green mould Penicillium digitatum. BE27 is able to enter into the cytosol and kill fungal cells. The mechanism of action seems to involve ribosomal RNA N-glycosylase activity on the sarcin-ricin loop of the major rRNA which inactivates irreversibly the fungal ribosomes. A structural motif composed of an alpha-helix and a beta-hairpin at the C-terminus of BE27 might contribute to the interaction with the fungal plasma membranes
cinnamomin potently inhibits the in vitro protein synthesis in the rabbit reticulocyte lysate system or a reconstituted protein synthesis system composed of rat ribosome with IC50 value of about 9.7 nM. The cleavage of supercoiled double-stranded DNA is an intrinsic property of cinnamomin A-chain, its N- and C-terminal regions are required for deadenylation of rRNA and also necessary for deadenylation of supercoiled double-stranded circular DNA
In Spiroplasma-containing Drosophila melanogaster, parasitic wasp ribosomes show abundant site-specific depurination in the alpha-sarcin/ricin loop of the 28S rRNA, with depurination occurring soon after wasp eggs hatch inside fly larvae. The pupal ectoparasitic wasp, Pachycrepoideus vindemmiae, escapes protection by Spiroplasma poulsonii, and its ribosomes do not show high levels of depurination. Drosophila melanogaster host ribosomes show little evidence of targeting by Spiroplasma poulsonii ribosome-inactivating proteins
treatment with enzyme causes 1.7fold and 1.4fold increases in the growth rate of root system upon carborundum-based application on the root growth medium of Nicotiana glutinosa
treatment with the enzyme significantly inhibits Caenorhabditis elegans development and results in worm cell apoptosis. Amino acid residues, Glu195, Asn81, Ala82, Tyr83, Glu164, Ser163, Ile159 and Arg167, play critical roles in the catalytic process
trichosanthin is highly toxic to trophoblasts and choriocarcinoma cells. Low-density lipoprotein receptor-related protein 1 is an essential receptor for trichosanthin in 2-choriocarcinoma cell lines
Corynebacterium diphtheriae secretes the diphtheria toxin, a virulence factor that can be lethal to the human organism at doses below 0.0001 mg/kg of body weight. During infections, the toxin binds to the cell membrane and subunit A will enter the cytoplasm and catalyze the ADP-ribosylation and inactivation of elongation factor 2 thus killing the eukaryotic cell by inhibiting ribosomal translocation
Shiga toxins (Stx) expressed in the intestinal lumen during infection with Shiga-toxigenic Escherichia coli must translocate across the epithelium and enter the systemic circulation to cause systemic (pathological) effects, including hemolytic uremic syndrome. Even though Stxs are potent protein synthesis inhibitors, both isoforms Stx1 and Stx2 have been shown to upregulate interleukin-8 protein expression in intestinal epithelial cells via the ribotoxic stress response, a signal transduction event resulting from specific damage to the 28S rRNA that causes activation of host stress-activated protein kinases. Stx1 and Stx2 are also capable of inducing MAPK activation in vitro