The DNA-alkylating metabolite tilimycin is a microbial genotoxin. Intestinal accumulation of tilimycin in individuals carrying til+ Klebsiella spp. causes apoptotic erosion of the epithelium and colitis.
View Article and Find Full Text PDFKlebsiella spp. that secrete the DNA-alkylating enterotoxin tilimycin colonize the human intestinal tract. Numbers of toxigenic bacteria increase during antibiotic use, and the resulting accumulation of tilimycin in the intestinal lumen damages the epithelium via genetic instability and apoptosis.
View Article and Find Full Text PDFGastrointestinal microbes respond to biochemical metabolites that coordinate their behaviors. Here, we demonstrate that bacterial indole functions as a multifactorial mitigator of Klebsiella grimontii and Klebsiella oxytoca pathogenicity. These closely related microbes produce the enterotoxins tilimycin and tilivalline; cytotoxin-producing strains are the causative agent of antibiotic-associated hemorrhagic colitis and have been associated with necrotizing enterocolitis of premature infants.
View Article and Find Full Text PDFObjective: Toxin-producing Klebsiella oxytoca causes antibiotic-associated haemorrhagic colitis (AAHC). The disease-relevant cytotoxins tilivalline and tilimycine produced by certain K. oxytoca isolates are encoded by the non-ribosomal peptide synthetase genes A (npsA) and B (npsB).
View Article and Find Full Text PDFMembers of the species complex (KoSC) are emerging human pathogens causing infections of increasing significance especially in healthcare settings. KoSC strains are affiliated with distinct phylogroups based on genetic variation at the beta-lactamase gene ( ) and it has been proposed that each major phylogroup represents a unique species. However, since the typing methods applied in clinical settings cannot differentiate every species within the complex, existing clinical, epidemiological and DNA sequence data is frequently misclassified.
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