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非热量人工甜味剂调节肠道微生物群中多药耐药质粒的偶联转移

发布者:抗性基因网 时间:2023-06-09 浏览量:278

摘要
      无热量人工甜味剂已被广泛允许作为具有高甜度的食糖替代品。它们可以在没有显著代谢的情况下通过肠道,并经常遇到肠道微生物组,肠道微生物组由多种细菌组成,是抗生素耐药性基因库。然而,人们对这些甜味剂是否会加速ARGs在肠道微生物组中的传播知之甚少。在这里,我们使用携带染色体插入的Tn7-lacIq-pLpp-mCherry和质粒编码的gfpmut3b基因的大肠杆菌作为供体,并使用小鼠粪便细菌作为受体,建立了体外接合模型。我们发现,四种常用的人工甜味剂(糖精、三氯蔗糖、阿斯巴甜和安赛蜜钾)可以增加活性氧(ROS)的产生,并促进质粒介导的偶联转移到肠道微生物组。粪便样本的细胞分选和16S rRNA基因扩增子测序分析表明,测试的甜味剂可以促进对革兰氏阴性和革兰氏阳性肠道细菌的广泛宿主范围的质粒允许性。增加的质粒允许性也用人类病原体肺炎克雷伯菌进行了验证。总之,我们的研究表明,无热量人工甜味剂可以诱导氧化应激,并促进肠道微生物群和人类病原体之间ARGs的质粒介导的偶联转移。考虑到这些甜味剂的消费量飙升以及人类肠道中流动ARG的丰富,我们的研究结果强调了对使用人工甜味剂作为食品添加剂的抗生素耐药性进行彻底风险评估的必要性。
ABSTRACT
Non-caloric artificial sweeteners have been widely permitted as table sugar substitutes with high intensities of sweetness. They can pass through the intestinal tract without significant metabolization and frequently encounter the gut microbiome, which is composed of diverse bacterial species and is a pool of antibiotic resistance genes (ARGs). However, little is known about whether these sweeteners could accelerate the spread of ARGs in the gut microbiome. Here, we established an in vitro conjugation model by using Escherichia coli that carries chromosome-inserted Tn7 lacIq-pLpp-mCherry and plasmid-encoded gfpmut3b gene as the donor and murine fecal bacteria as the recipient. We found that four commonly used artificial sweeteners (saccharin, sucralose, aspartame, and acesulfame potassium) can increase reactive oxygen species (ROS) production and promote plasmid-mediated conjugative transfer to the gut microbiome. Cell sorting and 16S rRNA gene amplicon sequencing analysis of fecal samples reveal that the tested sweeteners can promote the broad-host-range plasmid permissiveness to both Gram-negative and Gram-positive gut bacteria. The increased plasmid permissiveness was also validated with a human pathogen Klebsiella pneumoniae. Collectively, our study demonstrates that non-caloric artificial sweeteners can induce oxidative stress and boost the plasmid-mediated conjugative transfer of ARGs among the gut microbiota and a human pathogen. Considering the soaring consumption of these sweeteners and the abundance of mobile ARGs in the human gut, our results highlight the necessity of performing a thorough risk assessment of antibiotic resistance associated with the usage of artificial sweeteners as food additives.

https://www.tandfonline.com/doi/full/10.1080/19490976.2022.2157698