ClpB protein regulates biofilm formation in Methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) biofilms contribute significantly to chronic infections and treatment failure. The chaperone protein ClpB has been implicated in bacterial stress responses, but its role in MRSA biofilm regulation and toxicity remains unclear. We constructed a clpB knockout strain (ΔclpB) in MRSA USA300 and quantitatively compared its biofilm phenotype to the wild type (WT) using crystal violet staining, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and extracellular matrix (eDNA, polysaccharide, protein). A mouse skin infection model was used to evaluate wound healing, histopathology (H&E staining), and host inflammatory response (TNF-α/IL-6 ELISA and RT-PCR). ΔclpB showed significantly reduced biofilm biomass (p < 0.0001) and impaired three-dimensional structure with reduced extracellular matrix composition. In vivo, mice infected with ΔclpB showed accelerated wound closure, less severe tissue damage, and reduced levels of TNF-α and IL-6 at protein and transcription levels compared to controls infected with WT. ClpB is a key regulator of MRSA biofilm formation and toxicity, possibly by regulating extracellular matrix and host inflammation. Targeting ClpB could represent a novel anti-biofilm strategy against MRSA infections.

耐甲氧西林金黄色葡萄球菌（Methicillin-resistant Staphylococcus aureus, MRSA）生物膜可显著促成慢性感染与治疗失败。伴侣蛋白ClpB已被证实参与细菌应激反应，但其在MRSA生物膜调控及致病毒性中的作用仍不明确。本研究在MRSA USA300菌株中构建了clpB基因敲除菌株（ΔclpB），并通过结晶紫染色、扫描电子显微镜（SEM）、共聚焦激光扫描显微镜（CLSM）及细胞外基质（包括细胞外DNA、多糖与蛋白质）分析，定量对比了该敲除株与野生型（WT）菌株的生物膜表型。此外，本研究利用小鼠皮肤感染模型评估了伤口愈合情况、组织病理学（苏木精-伊红（H&E）染色）及宿主炎症反应（采用肿瘤坏死因子-α/白细胞介素-6 ELISA与逆转录聚合酶链反应（RT-PCR）检测）。结果显示，ΔclpB菌株的生物膜生物量显著降低（p < 0.0001），三维结构受损且细胞外基质含量减少。体内实验中，与野生型感染对照组相比，ΔclpB感染组小鼠的伤口闭合速度更快、组织损伤程度更轻，且肿瘤坏死因子-α与白细胞介素-6的蛋白表达水平及转录水平均有所降低。综上，ClpB是MRSA生物膜形成与致病毒性的关键调控因子，其作用可能通过调控细胞外基质生成及宿主炎症反应实现。靶向ClpB或可成为对抗MRSA感染的新型抗生物膜治疗策略。

搜集汇总

背景与挑战

背景概述

该数据集研究ClpB蛋白在耐甲氧西林金黄色葡萄球菌（MRSA）生物膜形成和毒性中的作用。通过敲除clpB基因的实验发现，ΔclpB菌株的生物膜生物量和结构显著减少，且在小鼠感染模型中表现出伤口愈合加快和炎症反应降低。结果表明ClpB是调控MRSA生物膜的关键因子，可能成为抗感染治疗的新靶点。