Dataset Information

Microbial biotransformation of DON: molecular basis for reduced toxicity.

ABSTRACT: Bacteria are able to de-epoxidize or epimerize deoxynivalenol (DON), a mycotoxin, to deepoxy-deoxynivalenol (deepoxy-DON or DOM-1) or 3-epi-deoxynivalenol (3-epi-DON), respectively. Using different approaches, the intestinal toxicity of 3 molecules was compared and the molecular basis for the reduced toxicity investigated. In human intestinal epithelial cells, deepoxy-DON and 3-epi-DON were not cytotoxic, did not change the oxygen consumption or impair the barrier function. In intestinal explants, exposure for 4?hours to 10??M DON induced intestinal lesions not seen in explants treated with deepoxy-DON and 3-epi-DON. A pan-genomic transcriptomic analysis was performed on intestinal explants. 747 probes, representing 323 genes, were differentially expressed, between DON-treated and control explants. By contrast, no differentially expressed genes were observed between control, deepoxy-DON and 3-epi-DON treated explants. Both DON and its biotransformation products were able to fit into the pockets of the A-site of the ribosome peptidyl transferase center. DON forms three hydrogen bonds with the A site and activates MAPKinases (mitogen-activated protein kinases). By contrast deepoxy-DON and 3-epi-DON only form two hydrogen bonds and do not activate MAPKinases. Our data demonstrate that bacterial de-epoxidation or epimerization of DON altered their interaction with the ribosome, leading to an absence of MAPKinase activation and a reduced toxicity.

SUBMITTER: Pierron A

PROVIDER: S-EPMC4933977 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Microbial biotransformation of DON: molecular basis for reduced toxicity.

Pierron Alix A Mimoun Sabria S Murate Leticia S LS Loiseau Nicolas N Lippi Yannick Y Bracarense Ana-Paula F L AP Schatzmayr Gerd G He Jian Wei JW Zhou Ting T Moll Wulf-Dieter WD Oswald Isabelle P IP

Scientific reports 20160706

Bacteria are able to de-epoxidize or epimerize deoxynivalenol (DON), a mycotoxin, to deepoxy-deoxynivalenol (deepoxy-DON or DOM-1) or 3-epi-deoxynivalenol (3-epi-DON), respectively. Using different approaches, the intestinal toxicity of 3 molecules was compared and the molecular basis for the reduced toxicity investigated. In human intestinal epithelial cells, deepoxy-DON and 3-epi-DON were not cytotoxic, did not change the oxygen consumption or impair the barrier function. In intestinal explant ...[more]

PMID: 27381510

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Dataset Information

Microbial biotransformation of DON: molecular basis for reduced toxicity.

Publications

Microbial biotransformation of DON: molecular basis for reduced toxicity.

Similar Datasets

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