Phenol and -cresol are two common toxic small molecules related to various diseases. Existing reports confirmed that high -tyrosine in the daily diet can increase the concentration of phenolic compounds in blood and urine. L-tyrosine is a common component of protein-rich foods. Some anaerobic bacteria in the gut can convert non-toxic l-tyrosine into these two toxic phenolic compounds, phenol and -cresol. Existing methods have been constructed for measuring the concentration of phenolic compound in feces. However, there is still a lack of direct visual evidence to measure the phenolic compounds in the intestine. In this study, we aimed to construct a whole-cell biosensor for phenolic compounds detection based on the , the regulator from the phenol metabolism cluster. The commensal bacterium PS01 was selected and used as the chassis. Compared with the biosensor based on ECN1917, the biosensor PS01[] could better implant into the mouse gut through gavage and showed a higher sensitive to phenolic compound. And the concentration of phenolic compounds in the intestines could be observed with the help of imaging system using PS01[]. This paper demonstrated endogenous phenol synthesis in the gut and the strategy of using commensal bacteria to construct whole-cell biosensors for detecting small molecule compounds in the intestines.

中文翻译：

---

肠道内源性有毒酚类化合物的体内检测


苯酚和对甲酚是两种常见的有毒小分子，与多种疾病有关。现有报道证实，日常饮食中高酪氨酸可以增加血液和尿液中酚类化合物的浓度。 L-酪氨酸是富含蛋白质的食物的常见成分。肠道中的一些厌氧细菌可以将无毒的L-酪氨酸转化为这两种有毒的酚类化合物：苯酚和对甲酚。已经建立了现有的方法来测量粪便中酚类化合物的浓度。然而，仍然缺乏直接的视觉证据来测量肠道中的酚类化合物。在本研究中，我们的目的是基于苯酚代谢簇的调节因子构建用于酚类化合物检测的全细胞生物传感器。选择共生菌PS01作为底盘。与基于ECN1917的生物传感器相比，生物传感器PS01[]可以通过灌胃更好地植入小鼠肠道，并对酚类化合物表现出更高的敏感性。借助PS01[]的成像系统可以观察肠道内酚类化合物的浓度。本文展示了肠道内源性苯酚的合成以及利用共生细菌构建全细胞生物传感器来检测肠道内小分子化合物的策略。