Gut microbes play a crucial role in the maintenance of human health. Components in the diet of the host affect their metabolism and diversity. Here, we investigated the influences of three commonly used non-caloric artificial sweeteners-aspartame, acesulfame K and sucralose-on the growth and metabolism of an omnipresent gut microbe Escherichia coli K-12. Methods: Growth of E. coli in the presence of aspartame, acesulfame K and sucralose in media was assessed and the influences of these artificial sweeteners on metabolism were investigated by relative expression analysis of genes encoding the rate limiting steps of important metabolic pathways as well as their global metabolomic profiles. Results: As a whole, E. coli growth was inhibited by aspartame and induced by acesulfame potassium, while the effect of sucralose on growth was less prominent. Although the expressions of multiple key enzymes that regulate important metabolic pathways were significantly altered by all three sweeteners, acesulfame K caused the most notable changes in this regard. In multivariate analysis with the metabolite profiles, the sucralose-treated cells clustered the closest to the untreated cells, while the acesulfame potassium treated cells were the most distant. These sweeteners affect multiple metabolic pathways in E. coli, which include propanoate, phosphonate, phosphinate and fatty acid metabolism, pentose phosphate pathway, and biosynthesis of several amino acids including lysine and the aromatic amino acids. Similar to the gene expression pattern, acesulfame potassium treated E. coli showed the largest deviation in their metabolite profiles compared to the untreated cells.

中文翻译：

---

阿斯巴甜、安赛蜜和三氯蔗糖——对大肠杆菌代谢的影响。

肠道微生物在维持人类健康中发挥着至关重要的作用。宿主饮食中的成分影响其新陈代谢和多样性。在这里，我们研究了三种常用的无热量人造甜味剂——阿斯巴甜、安赛蜜和三氯蔗糖——对无所不在的肠道微生物大肠杆菌 K-12 生长和代谢的影响。方法：评估了大肠杆菌在存在阿斯巴甜、安赛蜜和三氯蔗糖的培养基中的生长情况，并通过编码重要代谢途径限速步骤的基因的相对表达分析来研究这些人工甜味剂对代谢的影响以及他们的全球代谢组图谱。结果：总体而言，阿斯巴甜对大肠杆菌生长有抑制作用，安赛蜜对大肠杆菌生长有诱导作用，而三氯蔗糖对生长的影响不太明显。尽管所有三种甜味剂都显着改变了调节重要代谢途径的多种关键酶的表达，但安赛蜜在这方面引起了最显着的变化。在代谢物谱的多变量分析中，三氯蔗糖处理的细胞与未处理的细胞最接近，而安赛蜜处理的细胞距离最远。这些甜味剂影响大肠杆菌中的多种代谢途径，包括丙酸、膦酸、次膦酸和脂肪酸代谢、戊糖磷酸途径以及包括赖氨酸和芳香族氨基酸在内的多种氨基酸的生物合成。与基因表达模式类似，与未处理的细胞相比，经安赛蜜处理的大肠杆菌的代谢物谱显示出最大的偏差。