Dataset Information

Gut Microbial Transformation of the Dietary Imidazoquinoxaline Mutagen MelQx Reduces Its Cytotoxic and Mutagenic Potency.

ABSTRACT: The diverse community of microbes present in the human gut has emerged as an important factor for cancer risk, potentially by altering exposure to chemical carcinogens. In the present study, human gut bacteria were tested for their capacity to transform the carcinogenic heterocyclic amine 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MelQx). Eubacterium hallii, Lactobacillus reuteri, and Lactobacillus rossiae were able to convert MelQx to a new microbial metabolite characterized on the basis of high-resolution mass spectrometry and NMR as 9-hydroxyl-2,7-dimethyl-7,9,10,11-tetrahydropyrimido[2',1':2,3]imidazo[4,5-f]quinoxaline (MelQx-M1), resulting from conjugation with activated glycerol. Acrolein derived from the decomposition of 3-hydroxypropionaldehyde, which is the product of bacterial glycerol/diol dehydratase activity, was identified as the active compound responsible for the formation of MelQx-M1. A complex human gut microbial community obtained from invitro continuous intestinal fermentation was found to also transform MelQx to MelQx-M1. MelQx-M1 had slightly reduced cytotoxic potency toward human colon epithelial cells invitro, and diminished mutagenic potential toward bacteria after metabolic activation. As bacterially derived acrolein also transformed 2 other HCAs, namely 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine and 2-amino-3-methylimidazo[4,5-f]quinoline, these results generalize the capacity of gut microbiota to detoxify HCAs in the gut, potentially modulating cancer risk.

SUBMITTER: Zhang J

PROVIDER: S-EPMC5837702 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Gut Microbial Transformation of the Dietary Imidazoquinoxaline Mutagen MelQx Reduces Its Cytotoxic and Mutagenic Potency.

Zhang Jianbo J Empl Michael T MT Schwab Clarissa C Fekry Mostafa I MI Engels Christina C Schneider Mirjam M Lacroix Christophe C Steinberg Pablo P Sturla Shana J SJ

Toxicological sciences : an official journal of the Society of Toxicology 20170901 1

The diverse community of microbes present in the human gut has emerged as an important factor for cancer risk, potentially by altering exposure to chemical carcinogens. In the present study, human gut bacteria were tested for their capacity to transform the carcinogenic heterocyclic amine 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MelQx). Eubacterium hallii, Lactobacillus reuteri, and Lactobacillus rossiae were able to convert MelQx to a new microbial metabolite characterized on the basis of ...[more]

PMID: 28666384

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Dataset Information

Gut Microbial Transformation of the Dietary Imidazoquinoxaline Mutagen MelQx Reduces Its Cytotoxic and Mutagenic Potency.

Publications

Gut Microbial Transformation of the Dietary Imidazoquinoxaline Mutagen MelQx Reduces Its Cytotoxic and Mutagenic Potency.

Similar Datasets

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