Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Engineering Research Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China.
School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, 72# Jimo Binhai Road, Qingdao, Shandong, 266237, P.R. China.
Sci Rep. 2019 Aug 2;9(1):11253. doi: 10.1038/s41598-019-46833-1.
In this research, antibiotic-producing bacteria, Streptomyces coelicolor (S. coelicolor) M145, was exposed to copper oxide (CuO) particles to investigate the effects of nano-particles (NPs) on antibiotic production. Results showed that a higher yield of antibiotics was obtained with smaller particle sizes of CuO NPs. When exposed to 10 mg/L of 40 nm CuO NPs, the maximum amount of actinorhodin (ACT) obtained was 2.6 mg/L after 144 h, which was 2.0-fold greater than that of control. However, the process was inhibited when the concentration of CuO NPs was increased to higher than 20 mg/L. Transcriptome analysis showed that all the genes involved in the ACT cluster were significantly up-regulated after exposure to 10 mg/L NPs, which could be the direct cause of the increase of ACT production. Additionally, some genes related to the generation of acetyl-coA were up-regulated. In this way, CuO NPs led to an increase of secondary metabolites. The mechanism related to these changes indicated that nano-particle‒induced ROS and Cu played synergetic roles in promoting ACT biosynthesis. This is a first report suggesting that CuO NPs had a significant effect on antibiotic production, which will be helpful in understanding the mechanism of antibiotic production in nature.
在这项研究中，研究人员将产抗生素细菌变铅青链霉菌（Streptomyces coelicolor，S. coelicolor）M145 暴露于氧化铜（CuO）颗粒中，以研究纳米颗粒（NPs）对抗生素产生的影响。结果表明，CuO NPs 的粒径越小，抗生素的产量越高。当暴露于 10mg/L、粒径为 40nm 的 CuO NPs 时，经过 144 小时后获得的放线紫红素（ACT）的最大产量为 2.6mg/L，是对照的 2.0 倍。然而，当 CuO NPs 的浓度增加到高于 20mg/L 时，该过程受到抑制。转录组分析表明，暴露于 10mg/L NPs 后，与 ACT 簇相关的所有基因均显著上调，这可能是 ACT 产量增加的直接原因。此外，一些与乙酰辅酶 A 生成相关的基因也上调。这样，CuO NPs 导致了次生代谢物的增加。与这些变化相关的机制表明，纳米颗粒诱导的 ROS 和 Cu 协同促进了 ACT 生物合成。这是首次报道表明 CuO NPs 对抗生素产生有显著影响，这将有助于理解自然界中抗生素产生的机制。
