Department of Infectious Diseases and the Key Lab of Endogenous Infection, Shenzhen Nanshan People's Hospital, the 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China.
National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Medicine, Shenzhen University, Shenzhen, China.
Microbiol Spectr. 2022 Apr 27;10(2):e0054121. doi: 10.1128/spectrum.00541-21. Epub 2022 Mar 2.
Staphylococcus aureus poses a significant threat to human health due to its virulence and multidrug resistance. In addition, recalcitrant biofilm formation of S. aureus often results in chronic infection and the treatment tolerance toward the traditional antibiotics. Thus, the development of novel antimicrobial agents capable to inhibit or eradicate S. aureus biofilm formation does matter. Here, we demonstrated that clemastine showed slight bacteriostatic activity and enhanced the antibacterial activity of oxacillin against S. aureus. Moreover, the dramatic inhibition of biofilm formation was found in clinical S. aureus strains by clemastine. Clemastine inhibited the release of eDNA during the biofilm formation and decreased the S. aureus hemolytic activity. Moreover, the S. aureus SA113 treated with clemastine displayed the decreased transcriptional level of the biofilm formation relevant genes (, , and ), virulence genes (, , , and ), and the regulatory genes . The proteomics analysis of SA113 treated with clemastine demonstrated the significant changes in levels of biofilm-related proteins (stress response regulators ClpB and GroS, ATP-binding proteins, and urease metabolism), virulence-related proteins (SspA, superantigen, and VWbp), and methicillin resistance-related proteins (glutamine metabolism). The genetic mutations on (cyclic di-AMP phosphodiesterase) were found in the clemastine-induced tolerant derivative isolate by whole-genome sequencing. Furthermore, the interaction between clemastine and GdpP protein was demonstrated by the molecular docking, overexpression experiment, and thermal stability assay. Conclusively, clemastine might exert its inhibitory effects against the biofilm formation and hemolysis in S. aureus through targeting GdpP protein. The biofilm formation, which protects bacteria from stresses, including antibiotics and host immune responses, can be commonly found in clinical S. aureus isolates worldwide. Treatment failure of traditional antibiotics in biofilm-associated S. aureus infections remains a serious challenge. The novel anti-biofilm drug is urgently needed to address the looming crisis. In this study, clemastine, which is a histamine receptor H1 (HRH1) antagonist, was found to have a novel role of the significant inhibition against the biofilm formation and hemolytic activity of S. aureus and enhanced antibacterial activity against S. aureus when used in combination with oxacillin by targeting the GdpP protein. The discovery of this study identified novel use and mechanism of action of clemastine as a potential anti-biofilm drug for clinical application for S. aureus infectious.
金黄色葡萄球菌由于其毒力和多药耐药性，对人类健康构成重大威胁。此外，金黄色葡萄球菌顽固的生物膜形成常常导致慢性感染和对传统抗生素的治疗耐受。因此，开发能够抑制或消除金黄色葡萄球菌生物膜形成的新型抗菌剂非常重要。在这里，我们证明了氯马斯汀表现出轻微的抑菌活性，并增强了苯唑西林对金黄色葡萄球菌的抗菌活性。此外，氯马斯汀显著抑制了临床金黄色葡萄球菌菌株的生物膜形成。氯马斯汀抑制生物膜形成过程中 eDNA 的释放，并降低金黄色葡萄球菌的溶血活性。此外，用氯马斯汀处理的金黄色葡萄球菌 SA113 显示出生物膜形成相关基因（、、和）、毒力基因（、、、和）和调节基因的转录水平降低。用氯马斯汀处理的 SA113 的蛋白质组学分析表明，生物膜相关蛋白（应激反应调节剂 ClpB 和 GroS、ATP 结合蛋白和脲酶代谢）、毒力相关蛋白（SspA、超抗原和 VWbp）和耐甲氧西林相关蛋白（谷氨酰胺代谢）的水平发生了显著变化。全基因组测序发现，在氯马斯汀诱导的耐受衍生分离株中，发现了对基因（环二核苷酸磷酸二酯酶）的基因突变。此外，通过分子对接、过表达实验和热稳定性测定证实了氯马斯汀与 GdpP 蛋白的相互作用。结论：氯马斯汀可能通过靶向 GdpP 蛋白，发挥其抑制金黄色葡萄球菌生物膜形成和溶血的作用。生物膜形成使细菌能够抵抗抗生素和宿主免疫反应等应激，在世界各地的临床金黄色葡萄球菌分离株中都很常见。传统抗生素在生物膜相关金黄色葡萄球菌感染中的治疗失败仍然是一个严重的挑战。急需新型抗生物膜药物来应对迫在眉睫的危机。在这项研究中，发现氯马斯汀作为一种组胺受体 H1（HRH1）拮抗剂，具有通过靶向 GdpP 蛋白抑制金黄色葡萄球菌生物膜形成和溶血以及增强苯唑西林对金黄色葡萄球菌的抗菌活性的新作用。这项研究的发现确定了氯马斯汀作为一种潜在的抗生物膜药物用于金黄色葡萄球菌感染的临床应用的新用途和作用机制。
