PDF(Pubmed)
Abstract：
Mitochondria-targeted antioxidants (MTAs) have been studied quite intensively in recent years as potential therapeutic agents and vectors for the delivery of other active substances to mitochondria and bacteria. Their most studied representatives are MitoQ and SkQ1, with its fluorescent rhodamine analog SkQR1, a decyl ester of rhodamine 19 carrying plastoquinone. In the present work, we observed a pronounced antibacterial action of SkQR1 against Gram-positive bacteria, but virtually no effect on Gram-negative bacteria. The MDR pump AcrAB-TolC, known to expel SkQ1, did not recognize and did not pump out SkQR1 and dodecyl ester of rhodamine 19 (C12R1). Rhodamine 19 butyl (C4R1) and ethyl (C2R1) esters more effectively suppressed the growth of ΔtolC Escherichia coli, but lost their potency with the wild-type E. coli pumping them out. The mechanism of the antibacterial action of SkQR1 may differ from that of SkQ1. The rhodamine derivatives also proved to be effective antibacterial agents against various Gram-positive species, including Staphylococcus aureus and Mycobacterium smegmatis. By using fluorescence correlation spectroscopy and fluorescence microscopy, SkQR1 was shown to accumulate in the bacterial membrane. Thus, the presentation of SkQR1 as a fluorescent analogue of SkQ1 and its use for visualization should be performed with caution.
摘要：
近年来，针对线粒体的抗氧化剂（MTA）作为将其他活性物质递送至线粒体和细菌的潜在治疗剂和载体已被深入研究。他们研究最多的代表是MitoQ和SkQ1，其荧光罗丹明类似物SkQR1是罗丹明19的癸基酯，带有塑性醌。在目前的工作中,我们观察到SkQR1对革兰氏阳性细菌的明显抗菌作用，但对革兰氏阴性菌几乎没有影响.MDR泵AcrAB-TolC，已知驱逐SkQ1，不识别也没有抽出SkQR1和罗丹明19的十二烷基酯（C12R1）。罗丹明19丁基（C4R1）和乙基（C2R1）酯更有效地抑制了ΔtolC大肠杆菌的生长，但是野生型大肠杆菌把它们抽出来就失去了效力。SkQR1的抗菌作用机制可能与SkQ1不同。罗丹明衍生物还被证明是针对各种革兰氏阳性物种的有效抗菌剂，包括金黄色葡萄球菌和耻垢分枝杆菌。利用荧光相关光谱和荧光显微镜,显示SkQR1在细菌膜中积累。因此，应谨慎使用SkQR1作为SkQ1的荧光类似物及其可视化用途.
