School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China.
School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Hangzhou 310012, China.
Environ Pollut. 2020 Feb;257:113352. doi: 10.1016/j.envpol.2019.113352. Epub 2019 Oct 12.
The interference of nonylphenol (NP) with humans and animals, especially in hormone systems, has been well-studied. There is rarely any record of its effect on bacteria, which dominate in various environments. In our study, we employed Pseudomonas aeruginosa PAO1 as a model microorganism and took its common lifestyle biofilm, mainly regulated by quorum sensing (QS), as a cut-in point to investigate the effect of NP (1, 5, 10 mg L) on bacteria. The results showed that more than 5 mg L of NP did interfere with biofilm formation and affected bacterial QS. In detail, the LasI/R circuit, but not the RhlI/R circuit, was considerably obstructed. The decrease in lasI and lasR expression resulted in a significant reduction in N-3-oxo-dodecanoyl homoserine lactone (3OC-HSL) signals and the downstream production of elastases. Docking results indicated the binding of NP with LasR protein, simulating the binding of 3OC-HSL with LasR protein, which explained the obstruction of the LasIR circuit. We concluded that NP competed with 3OC-HSL and blocked 3OC-HSL binding with the LasR protein, resulting in a direct interference in bacterial biofilm formation. This is the first report of NP interference with bacterial signaling, which is not only helpful to understand the effect of NP on various ecosystems, but is also beneficial to enrich our knowledge of inter-kingdom communication.
壬基酚（NP）对人类和动物的干扰，尤其是对激素系统的干扰，已经得到了充分的研究。然而，关于它对细菌的影响却很少有记录，因为细菌在各种环境中占主导地位。在我们的研究中，我们以铜绿假单胞菌 PAO1 为模型微生物，以其常见的生活方式生物膜（主要由群体感应（QS）调节）为切入点，研究 NP（1、5、10mg/L）对细菌的影响。结果表明，超过 5mg/L 的 NP 会干扰生物膜的形成并影响细菌的 QS。具体来说，LasI/R 回路受到了相当大的阻碍，而不是 RhlI/R 回路。LasI 和 lasR 表达的减少导致 N-3-氧代-十二酰高丝氨酸内酯（3OC-HSL）信号显著减少，下游弹性蛋白酶的产生也减少。对接结果表明 NP 与 LasR 蛋白结合，模拟了 3OC-HSL 与 LasR 蛋白的结合，这解释了 LasIR 回路的阻塞。我们得出结论，NP 与 3OC-HSL 竞争并阻止 3OC-HSL 与 LasR 蛋白结合，从而直接干扰细菌生物膜的形成。这是首次报道 NP 干扰细菌信号，这不仅有助于理解 NP 对各种生态系统的影响，还有助于丰富我们对种间通讯的认识。
