Sianglum Wipawadee, Saeloh Dennapa, Tongtawe Pongsri, Wootipoom Natthakul, Indrawattana Nitaya, Voravuthikunchai Supayang Piyawan
1 Department of Microbiology and Excellence Research Laboratory on Natural Products, Faculty of Science and Natural Product Research Center of Excellence, Prince of Songkla University , Hat Yai, Thailand .
2 Faculty of Medical Technology, Prince of Songkla University , Hat Yai, Thailand .
Microb Drug Resist. 2018 Sep;24(7):882-889. doi: 10.1089/mdr.2016.0294. Epub 2017 Dec 7.
Strong evidence of high potency of rhodomyrtone as a promising antibacterial agent against pathogenic gram-positive bacteria has been clearly demonstrated in our previous work. The aim of this study was to provide insight into early action of rhodomyrtone, an acylphloroglucinol, on membrane damage in multidrug-resistant methicillin-resistant Staphylococcus aureus (MRSA). Early effects of rhodomyrtone on the bacterial membrane integrity were detected in a time-course study. Flow cytometry revealed a reduction in green fluorescent emission and increase in uptake of propidium iodide in rhodomyrtone-treated bacterial cells in a concentration- and time-dependent manner. Disruption of cytoplasmic membrane was further monitored by measuring cellular adenosine triphosphate (ATP) and potassium ion (K). Leakage of both ATP and K and significant decrease in intracellular ATP in MRSA were observed following treatment. Pronounced changes in the bacterial ultrastructure and morphology were confirmed by transmission electron microscopy and scanning electron microscopy. Bacterial cell disruption, holes in cell surface, and bulge formations were noted in rhodomyrtone-treated cells. In this study, we provided relevant data to clarify that rhodomyrtone is a bacterial cell membrane-damaging agent. A possible early effect of this novel compound involves bacterial membrane disruption.
在我们之前的工作中，已明确证明了玫红菌素作为一种有前景的抗革兰氏阳性病原菌抗菌剂具有高效力的有力证据。本研究的目的是深入了解酰基间苯三酚类化合物玫红菌素对多重耐药性耐甲氧西林金黄色葡萄球菌（MRSA）膜损伤的早期作用。在一项时间进程研究中检测了玫红菌素对细菌膜完整性的早期影响。流式细胞术显示，经玫红菌素处理的细菌细胞中绿色荧光发射减少，碘化丙啶摄取增加，呈浓度和时间依赖性。通过测量细胞三磷酸腺苷（ATP）和钾离子（K）进一步监测细胞质膜的破坏情况。处理后观察到MRSA中ATP和K的泄漏以及细胞内ATP的显著降低。通过透射电子显微镜和扫描电子显微镜证实了细菌超微结构和形态的明显变化。在经玫红菌素处理的细胞中发现了细菌细胞破裂、细胞表面孔洞和凸起形成。在本研究中，我们提供了相关数据以阐明玫红菌素是一种细菌细胞膜损伤剂。这种新型化合物可能的早期作用涉及细菌膜破坏。
