Department of Clinical Microbiology, Rennes University Hospital, Rennes, France.
Inserm UMR_S 1230, Bacterial Regulatory RNAs and Medicine, University of Rennes 1, Rennes, France.
Sci Rep. 2021 Mar 25;11(1):6892. doi: 10.1038/s41598-021-86376-y.
The aim of the study was to characterize the antimicrobial activity of clinically-relevant biocides (chlorhexidine digluconate, benzalkonium chloride, PVP-iodine and triclosan) and to determine the sRNA expression profiles under biocide exposure in two major bacterial opportunistic pathogens, Enterococcus faecium and Staphylococcus aureus. In vitro activities were evaluated against S. aureus HG003 and E. faecium Aus0004. We determined MIC, MBC, sub-inhibitory concentrations (SIC) and growth curves under SIC conditions. sRNA expression study under SIC exposure of biocides was performed by RT-qPCR on 3 sRNAs expressed in S. aureus (RNAIII, SprD and SprX) and the first 9 sRNAs identified as expressed in E. faecium. MICs were higher against E. faecium than for S. aureus. Growth curves under increasing biocide concentrations highlighted two types of bactericidal activity: "on/off" effect for chlorhexidine, benzalkonium chloride, PVP-iodine and a "concentration-dependent" activity for triclosan. Exposure to biocide SICs led to an alteration of several sRNA expression profiles, mostly repressed. The distinct biocide activity profiles must be evaluated with other compounds and bacterial species to enrich the prediction of resistance risks associated with biocide usage. Biocide exposure induces various sRNA-mediated responses in both S. aureus and E. faecium, and further investigations are needed to decipher sRNA-driven regulatory networks.
本研究旨在对临床相关消毒剂（洗必泰葡萄糖酸、苯扎氯铵、聚维酮碘和三氯生）的抗菌活性进行表征，并确定两种主要机会致病菌粪肠球菌和金黄色葡萄球菌在消毒剂暴露下的 sRNA 表达谱。体外活性评估针对金黄色葡萄球菌 HG003 和粪肠球菌 Aus0004。我们测定了 MIC、MBC、亚抑菌浓度 (SIC) 和 SIC 条件下的生长曲线。通过 RT-qPCR 在金黄色葡萄球菌（RNAIII、SprD 和 SprX）中表达的 3 个 sRNA 和鉴定为粪肠球菌表达的前 9 个 sRNA 下，对 SIC 暴露下的 sRNA 表达进行了研究。对粪肠球菌的 MIC 高于对金黄色葡萄球菌的 MIC。随着消毒剂浓度的增加，生长曲线突出了两种杀菌活性：洗必泰、苯扎氯铵、聚维酮碘的“开/关”效应和三氯生的“浓度依赖性”活性。SIC 暴露导致几个 sRNA 表达谱的改变，大多数受到抑制。必须用其他化合物和细菌对不同的消毒剂活性谱进行评估，以丰富与消毒剂使用相关的耐药风险预测。消毒剂暴露在金黄色葡萄球菌和粪肠球菌中诱导了各种 sRNA 介导的反应，需要进一步研究来破译 sRNA 驱动的调控网络。
