Background

The treatment of patients with Staphylococcus aureus infections mainly relies on antistaphylococcal regimens that are established with effective antibiotics. In antibiotic therapy or while living in nature, pathogens often face the sub-inhibitory concentrations (sub-MICs) of antibiotics due to drug pharmacokinetics, diffusion barriers, waste emission, resistant organism formation, and farming application. Different categories of antibiotics at sub-MICs have diverse effects on the physiological and chemical properties of microorganisms. These effects can result in virulence alterations. However, the mechanisms underlying the actions of antibiotics at sub-MICs on S. aureus virulence are obscure.

Aim of review

In this review, we focus on the effects of sub-MICs of antibiotics on S. aureus virulence from the aspects of cell morphological change, virulence factor expression, bacterial adherence and invasion, staphylococcal biofilm formation, and small-colony variant (SCV) production. The possible mechanisms of antibiotic-induced S. aureus virulence alterations are also addressed.

Key scientific concepts of review

Five main aspects of bacterial virulence can be changed in S. aureus exposure to the sub-MIC levels of antibiotics, resulting in deformed bacterial cells to stimulate abnormal host immune responses, abnormally expressed virulence factors to alter disease development, changed bacterial adhesion and invasion abilities to affect colonization and diffusion, altered biofilm formation to potentate material-related infections, and increased SCV formation to achieve persistent infection and recurrence. These advanced findings expand our knowledge to rethink the molecular signaling roles of antibiotics beyond their actions as antimicrobial agents.

中文翻译：

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亚抑制浓度抗生素治疗后金黄色葡萄球菌的毒力变化

背景

金黄色葡萄球菌感染患者的治疗主要依赖于使用有效抗生素建立的抗葡萄球菌治疗方案。在抗生素治疗中或生活在自然界中，由于药物药代动力学、扩散障碍、废物排放、抗性生物形成和农业应用，病原体经常面临抗生素的亚抑制浓度 (sub-MIC)。亚 MIC 的不同类别抗生素对微生物的生理和化学特性有不同的影响。这些作用可导致毒力改变。然而，抗生素在亚 MIC 对金黄色葡萄球菌毒力的作用机制尚不清楚。

审查的目的

在这篇综述中，我们从细胞形态变化、毒力因子表达、细菌粘附和侵袭、葡萄球菌生物膜形成和小菌落变异 (SCV) 产生等方面关注抗生素亚 MICs 对金黄色葡萄球菌毒力的影响。 . 还讨论了抗生素诱导的金黄色葡萄球菌毒力改变的可能机制。

审查的关键科学概念

细菌毒力的五个主要方面可以在金黄色葡萄球菌暴露于亚 MIC 水平的抗生素中发生改变，导致细菌细胞变形以刺激异常宿主免疫反应，异常表达的毒力因子改变疾病发展，改变细菌粘附和侵袭能力影响定植和扩散，改变生物膜形成以加强材料相关感染，并增加 SCV 形成以实现持续感染和复发。这些先进的发现扩展了我们的知识，以重新思考抗生素在其作为抗菌剂的作用之外的分子信号作用。