A growing body of evidence suggests that ribosome-inactivating proteins (RIPs) remove adenine moieties not only from rRNA, but also from DNA--an effect leading to DNA damage in cultured cells. We herein report that two distinct RIPs of bacterial (shiga toxin 1, Stx1) and plant (ricin) origin, inhibit the repair of the DNA lesions generated by hydrogen peroxide in cultured human cells. This effect is unrelated either to inhibition of protein synthesis or to depletion of cellular antioxidant defenses and is likely to derive from direct interactions with cellular DNA repair machinery. Therefore, the genotoxicity of these toxins on mammalian cells seems to be a complex phenomenon resulting from the balance between direct (DNA damaging activity), indirect (DNA repair inhibition) effects and the eventual presence of other DNA damaging species. In particular, with regard to Stx1, it could be hypothesized that Stx-producing bacteria increase the risk of transformation of surrounding, inflamed tissues in the course of human infections.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.dnarep.2004.09.007DOI Listing

Publication Analysis

Top Keywords

shiga toxin
8
inhibit repair
8
mammalian cells
8
dna repair
8
dna damaging
8
dna
7
toxin ricin
4
ricin inhibit
4
repair
4
repair h2o2-induced
4

Similar Publications

Characterization of Broad Spectrum Bacteriophage vB ESM-pEJ01 and Its Antimicrobial Efficacy Against Shiga Toxin-Producing in Green Juice.

Microorganisms

January 2025

Department of Food Science and Biotechnology, College of Bionano Technology, Gachon University, Seongnam 13120, Republic of Korea.

Shiga toxin-producing (STEC) infections have increased in humans, animals, and the food industry, with ready-to-eat (RTE) food products being particularly susceptible to contamination. The prevalence of multidrug-resistant strains has rendered the current control strategies insufficient to effectively control STEC infections. Herein, we characterized the newly isolated STEC phage vB_ESM-pEJ01, a polyvalent phage capable of infecting and species, and assessed its efficacy in reducing STEC in vitro and food matrices.

View Article and Find Full Text PDF

Viruses that infect cyanobacteria are an integral part of aquatic food webs, influencing nutrient cycling and ecosystem health. However, the significance of virus host range, replication efficiency, and host compatibility on cyanobacterial dynamics, growth, and toxicity remains poorly understood. In this study, we examined the effects of cyanophage additions on the dynamics and activity of optimal, sub-optimal, and non-permissive cyanobacterial hosts in cultures of Microcystis aeruginosa and Raphidiopsis raciborskii.

View Article and Find Full Text PDF

Hybrid strains of enterotoxigenic/Shiga toxin-producing , United Kingdom, 2014-2023.

J Med Microbiol

January 2025

NIHR Health Protection Research Unit in Gastrointestinal Infections, University of Liverpool, Liverpool, UK.

Diarrhoeagenic (DEC) pathotypes are defined by genes located on mobile genetic elements, and more than one definitive pathogenicity gene may be present in the same strain. In August 2022, UK Health Security Agency (UKHSA) surveillance systems detected an outbreak of hybrid Shiga toxin-producing /enterotoxigenic (STEC-ETEC) serotype O101:H33 harbouring both Shiga toxin () and heat-stable toxin (). These hybrid strains of DEC are a public health concern, as they are often associated with enhanced pathogenicity.

View Article and Find Full Text PDF

In July 2022, a genetically linked and geographically dispersed cluster of 12 cases of Shiga toxin-producing (STEC) O103:H2 was detected by the UK Health Security Agency using whole genome sequencing. Review of food history questionnaires identified cheese (particularly an unpasteurized brie-style cheese) and mixed salad leaves as potential vehicles. A case-control study was conducted to investigate exposure to these products.

View Article and Find Full Text PDF

Shiga toxin-producing Escherichia coli (STEC) infections pose a significant public health challenge, characterized by severe complications including hemolytic uremic syndrome (HUS) due to Shiga toxin (Stx) production. Current therapeutic approaches encounter a critical limitation, as conventional antibiotic treatment is contraindicated due to its propensity to trigger bacterial SOS response and subsequently enhance Stx production, which increases the likelihood of developing HUS in antibiotic-treated patients. The lack of effective, safe therapeutic options has created an urgent need for alternative treatment strategies for STEC infections.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!