Wasa Alibe, Aitken Jack, Jun Hyunwoo, Bishop Catherine, Krumdieck Susan, Godsoe William, Heinemann Jack A
School of Biological Sciences, University of Canterbury, Canterbury, New Zealand.
Department of Mechanical Engineering, University of Canterbury, Canterbury, New Zealand.
AMB Express. 2022 Sep 7;12(1):117. doi: 10.1186/s13568-022-01457-z.
Contaminated surfaces are vehicles for the spread of infectious disease-causing microorganisms. A strategy to prevent their spread is applying antimicrobial coatings to surfaces. Both nanostructured anatase rutile and carbon (NsARC), a TiO formulation, and copper are examples of antimicrobial agents that are used in making or coating door handles and similar surfaces, to reduce microbial loads. Antimicrobial surfaces have been extensively tested for antimicrobial activity but not sublethal effects, such as exposure-associated multiple antibiotic resistance phenotypes usually caused by induction of efflux pump genes. The possibility of NsARC and copper inducing indicative efflux pump pathways was investigated by monitoring the expression of mScarlet fluorescent protein (FP) in two reporter strains of Escherichia coli. There was an increase in the expression of FP in the reporter strains exposed to NsARC and copper relative to the inert control composed of stainless steel. Furthermore we tested E. coli and Staphylococcus aureus following 8 h of exposure to NsARC for changes in resistance to selected antibiotics. E. coli that were exposed to NsARC became more susceptible to kanamycin but there was no significant change in susceptibility of S. aureus to any tested antibiotics. These findings suggests that even though NsARC and copper are antimicrobial, they also have some potential to cause unintended phenotypes.
受污染的表面是传染病致病微生物传播的媒介。防止其传播的一种策略是在表面涂抹抗菌涂层。纳米结构锐钛矿金红石和碳（NsARC）（一种TiO配方）以及铜都是用于制造或涂覆门把手及类似表面以减少微生物负荷的抗菌剂实例。抗菌表面已针对抗菌活性进行了广泛测试，但尚未测试其亚致死效应，例如通常由外排泵基因诱导引起的与暴露相关的多重抗生素耐药表型。通过监测两种大肠杆菌报告菌株中mScarlet荧光蛋白（FP）的表达，研究了NsARC和铜诱导指示性外排泵途径的可能性。相对于由不锈钢组成的惰性对照，暴露于NsARC和铜的报告菌株中FP的表达有所增加。此外，我们测试了暴露于NsARC 8小时后的大肠杆菌和金黄色葡萄球菌对选定抗生素的耐药性变化。暴露于NsARC的大肠杆菌对卡那霉素变得更敏感，但金黄色葡萄球菌对任何测试抗生素的敏感性没有显著变化。这些发现表明，尽管NsARC和铜具有抗菌作用，但它们也有产生意外表型的可能性。
