低剂量氧化锌纳米颗粒触发铜绿假单胞菌的生长和生物膜形成：一种适应原反应。

Low-dose zinc oxide nanoparticles trigger the growth and biofilm formation of Pseudomonas aeruginosa: a hormetic response.

机构信息

Department of Microbiology, Pathology and Forensic Medicine, Faculty of Medicine, The Hashemite University, P.O box 330127, Zarqa, 13133, Jordan.

Department of Anatomy, Physiology and Biochemistry, Faculty of Medicine, The Hashemite University, P.O box 330127, Zarqa, 13133, Jordan.

出版信息

BMC Microbiol. 2024 Aug 3;24(1):290. doi: 10.1186/s12866-024-03441-y.

DOI:10.1186/s12866-024-03441-y

PMID:39095741

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11297655/

Abstract

INTRODUCTION

Hormesis describes an inverse dose-response relationship, whereby a high dose of a toxic compound is inhibitory, and a low dose is stimulatory. This study explores the hormetic response of low concentrations of zinc oxide nanoparticles (ZnO NPs) toward Pseudomonas aeruginosa.

METHOD

Samples of P. aeruginosa, i.e. the reference strain, ATCC 27,853, together with six strains recovered from patients with cystic fibrosis, were exposed to ten decreasing ZnO NPs doses (0.78-400 µg/mL). The ZnO NPs were manufactured from Peganum harmala using a chemical green synthesis approach, and their properties were verified utilizing X-ray diffraction and scanning electron microscopy. A microtiter plate technique was employed to investigate the impact of ZnO NPs on the growth, biofilm formation and metabolic activity of P. aeruginosa. Real-time polymerase chain reactions were performed to determine the effect of ZnO NPs on the expression of seven biofilm-encoding genes.

RESULT

The ZnO NPs demonstrated concentration-dependent bactericidal and antibiofilm efficiency at concentrations of 100-400 µg/mL. However, growth was significantly stimulated at ZnO NPs concentration of 25 µg/mL (ATCC 27853, Pa 3 and Pa 4) and at 12.5 µg/mL and 6.25 µg/mL (ATCC 27853, Pa 2, Pa 4 and Pa 5). No significant positive growth was detected at dilutions < 6.25 µg/mL. similarly, biofilm formation was stimulated at concentration of 12.5 µg/mL (ATCC 27853 and Pa 1) and at 6.25 µg/mL (Pa 4). At concentration of 12.5 µg/mL, ZnO NPs upregulated the expression of LasB ( ATCC 27853, Pa 1 and Pa 4) and LasR and LasI (ATCC 27853 and Pa 1) as well as RhII expression (ATCC 27853, Pa 2 and Pa 4).

CONCLUSION

When exposed to low ZnO NPs concentrations, P. aeruginosa behaves in a hormetic manner, undergoing positive growth and biofilm formation. These results highlight the importance of understanding the response of P. aeruginosa following exposure to low ZnO NPs concentrations.

摘要

简介

毒物兴奋效应描述了一种相反的剂量-反应关系，即高浓度的有毒化合物是抑制性的，而低浓度的则是刺激性的。本研究探讨了低浓度氧化锌纳米粒子（ZnO NPs）对铜绿假单胞菌的毒物兴奋效应。

方法

本研究选择铜绿假单胞菌（参考菌株 ATCC 27853）和从囊性纤维化患者中分离出的 6 株菌作为研究对象，暴露于 10 种逐渐降低的 ZnO NPs 剂量（0.78-400 µg/mL）中。ZnO NPs 是利用 Peganum harmala 采用化学绿色合成方法制造的，其性质通过 X 射线衍射和扫描电子显微镜进行了验证。采用微量滴定板技术研究了 ZnO NPs 对铜绿假单胞菌生长、生物膜形成和代谢活性的影响。实时聚合酶链反应用于确定 ZnO NPs 对 7 种生物膜编码基因表达的影响。

结果

ZnO NPs 在 100-400 µg/mL 浓度下表现出浓度依赖性的杀菌和抗生物膜效率。然而，在 ZnO NPs 浓度为 25 µg/mL（ATCC 27853、Pa 3 和 Pa 4）以及 12.5 µg/mL 和 6.25 µg/mL（ATCC 27853、Pa 2、Pa 4 和 Pa 5）时，生长显著受到刺激。在稀释度<6.25 µg/mL 时，未检测到明显的正生长。同样，在 12.5 µg/mL（ATCC 27853 和 Pa 1）和 6.25 µg/mL（Pa 4）时，生物膜形成受到刺激。在 12.5 µg/mL 时，ZnO NPs 上调了 LasB（ATCC 27853、Pa 1 和 Pa 4）和 LasR 和 LasI（ATCC 27853 和 Pa 1）以及 RhII 表达（ATCC 27853、Pa 2 和 Pa 4）。