Effect of ethanolamine utilization on the pathogenicity and metabolic profile of enterotoxigenic Escherichia coli
Effect of ethanolamine utilization on the pathogenicity and metabolic profile of enterotoxigenic Escherichia coli
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DOI：
10.1007/s00253-022-12261-x
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发表时间：
2022-11
影响因子：
5
通讯作者：
Xi Lu;Dingyan Wu;Xin Zhao;Mingxin Zhang;Ke Ren;Ningning Zhou;Yanni Zhao;Weisheng Qian
中科院分区：
文献类型：
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作者：
Xi Lu;Dingyan Wu;Xin Zhao;Mingxin Zhang;Ke Ren;Ningning Zhou;Yanni Zhao;Weisheng Qian
细菌的致病力在很大程度上取决于寄主微环境中营养物质的识别和利用。研究促进肠道病原菌毒力的肠道营养物质的特性有助于开发新的辅助治疗方法和抑制宿主损伤。乙醇胺(EA)作为肠道上皮细胞和细菌膜的主要成分，在肠道中含量丰富。在这里，我们首次证明了人和猪的关键病原菌肠毒素大肠杆菌(ETEC)可以利用EA作为氮源，从而影响其毒力表型。我们发现，与在M9(含NH_4Cl)中相比，EA对ETEC的生长有一定的抑制作用，但毒力相关基因的相对表达水平，如ltA(3.0倍)、fimH(2.9倍)、cfad(2.6倍)、gspD(3.6倍)和qesE(1.3倍)，以15 mM EA为氮源(P<； 0.05)显著增加，ETEC对Caco-2细胞的黏附效率增加约4.2倍。在Caco-2细胞中，电针(4 Mm)使细胞相对存活率从74.8%降至63.4%，跨上皮电阻值(TEER)降至74.8%。此外，电针可显著上调肿瘤坏死因子-α(3.2倍)、干扰素-γ(2.9倍)和IL-1β(1.98倍)等致炎因子的相对表达水平(P<； 0.0 5)，而在ΔeutR和ΔeutBETEC中未发现上述毒力变化。然后用气相色谱-质谱仪(GC-MS)的非靶向代谢组学方法揭示了EA诱导的与ETEC毒力相关的代谢重编程。结果表明，在0~15 mM的EA浓度范围内，ETEC中与碳水化合物、天冬氨酸和谷氨酸代谢、莽草酸代谢和丝氨酸代谢有关的大部分代谢物呈下降趋势，而支链氨基酸(BCAA)水平则呈剂量依赖性增加。结果表明，肠道EA浓度可显著影响ETEC的毒力表型、代谢特征和致病性。乙醇胺可调节ETEC的生长和毒力基因的表达。·EA肠道浓度促进ETEC对宿主上皮屏障的损伤作用。
Bacterial pathogenicity is greatly affected by nutrient recognition and utilization in the host microenvironment. The characterization of enteral nutrients that promote intestinal pathogen virulence is helpful for developing new adjuvant therapies and inhibiting host damage. Ethanolamine (EA), as a major component of intestinal epithelial cells and bacterial membranes, is abundant in the intestine. Here, we provide the first demonstration that the critical human and porcine pathogen enterotoxigenicEscherichia coli(ETEC) can utilize EA as a nitrogen source, which affects its virulence phenotype. We found that compared with that in M9 medium (containing NH4Cl), EA inhibited ETEC growth to a certain extent; however, the relative expression levels of virulence-related genes, such asltA(3.0-fold),fimH(2.9-fold),CfaD(2.6-fold),gspD(3.6-fold), andqesE(1.3-fold), increased significantly with 15 mM EA as a nitrogen source (P< 0.05), and the adhesion efficiency of ETEC to Caco-2 cells increased approximately 4.2-fold. In Caco-2 cells, the relative cell viability decreased from 74.8 to 63.4%, and the transepithelial electrical resistance (TEER) cells decreased to 74.8% with intestinal EA (4 mM). In addition, the relative expression levels of proinflammatory factors, such as TNF-α (3.2-fold), INF-γ (2.9-fold), and IL-1β (1.98-fold), in ETEC-infected Caco-2 cells were significantly upregulated (P< 0.05) under EA exposure; however, the above virulence changes were not found inΔeutRandΔeutBETEC. A gas chromatography–mass spectrometry (GC–MS)-based untargeted metabolomics approach was then employed to reveal EA-induced metabolic reprogramming related to ETEC virulence. The data showed that most metabolites related to carbohydrate, aspartate and glutamate metabolism, shikimic acid metabolism, and serine metabolism in ETEC exhibited a decreasing trend with increases in the EA concentration from 0 to 15 mM, but the branched-chain amino acid (BCAA) levels in ETEC increased in a dose-dependent manner under EA exposure. Our data suggest that the intestinal EA concentration can significantly affect the virulence phenotype, metabolic profile, and pathogenicity of ETEC.Key points•ETEC growth and virulence gene expression could be regulated by ethanolamine.•The intestinal concentration of EA promoted the damaging effect of ETEC on the host epithelial barrier.•The promoting effect of EA on ETEC toxicity may be related to BCAA metabolism.