Methicillin-resistant Staphylococcus aureus (MRSA) infections pose a serious threat worldwide. MRSA is the predominant species isolated from medical-device-related biofilm infections and chronic wounds. Its ability to form biofilms grants it resistance to almost all antibiotics on the market. Answering the call for alternative treatments, our lab has been investigating the efficacy of 600 Da branched polyethylenimine (BPEI) as a β-lactam potentiator against bacterial biofilms. Our previous study showed promise against methicillin-resistant Staphylococcus epidermidis biofilms. This study extends our previous findings to eradicate a more virulent pathogen: MRSA biofilms. Microtiter minimum biofilm eradication concentration models, crystal violet assays, and electron microscopy images show synergistic effects between BPEI and ampicillin as a two-step mechanism: step one is the removal of the extracellular polymeric substances (EPS) to expose individual bacteria targets, and step two involves electrostatic interaction of BPEI with anionic teichoic acid in the cell wall to potentiate the antibiotic.

中文翻译：

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低分子量支链聚乙烯亚胺增强氨苄青霉素抗MRSA生物膜的能力。

耐甲氧西林金黄色葡萄球菌（MRSA）感染在世界范围内构成了严重威胁。MRSA是从医疗设备相关的生物膜感染和慢性伤口中分离出来的主要物种。它具有形成生物膜的能力，使其对市场上几乎所有的抗生素都有抵抗力。为响应替代疗法的号召，我们的实验室一直在研究600 Da支链聚乙烯亚胺（BPEI）作为针对细菌生物膜的β-内酰胺增强剂的功效。我们以前的研究显示出抗甲氧西林表皮葡萄球菌生物膜的希望。这项研究扩展了我们先前的发现，以根除更具毒性的病原体：MRSA生物膜。微量滴定剂最小生物膜根除浓度模型，结晶紫测定，