Subinhibitory concentrations of licochalcone A decrease alpha-toxin production in both methicillin-sensitive and methicillin-resistant Staphylococcus aureus isolates
Subinhibitory concentrations of licochalcone A decrease alpha-toxin production in both methicillin-sensitive and methicillin-resistant Staphylococcus aureus isolates
复制标题
甘草查耳酮 A 的亚抑制浓度可减少甲氧西林敏感和耐甲氧西林金黄色葡萄球菌分离株中 α 毒素的产生
DOI：
10.1111/j.1472-765x.2009.02783.x
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发表时间：
2010-02-01
影响因子：
2.4
通讯作者：
Deng, X.
中科院分区：
文献类型：
--
作者：
Qiu, J.;Jiang, Y.;Deng, X.
目的：研究亚抑制浓度的地塞米松A(LICA)对金黄色葡萄球菌α-毒素分泌的影响。方法与结果：采用溶血素试验检测甲氧西林敏感和耐甲氧西林葡萄球菌培养上清液中的溶血活性。用分级亚抑制浓度的LICA培养的金黄色葡萄球菌分离物。免疫印迹法检测α-毒素分泌。定量RT-PCR检测LICA对α-毒素编码基因Hla和辅助基因调节因子AGR转录的影响。在LICA存在下的生长明显抑制葡萄球菌中Hla和AgR的mRNA水平。结论：金黄色葡萄球菌甲型毒素的分泌减少，从而降低了溶血活性。金黄色葡萄球菌被LICA减少；这一效应可能部分依赖于对AGR双组分系统的抑制。研究的意义和影响：我们研究的结果可能支持将LICA作为先导化合物用于设计更有效的基于查尔酮模板的抗菌剂。
Aim:To evaluate the effect of subinhibitory concentrations of licochalcone A (LicA) on alpha-toxin secretion in Staphylococcus aureus.Methods and Results:A haemolysin assay was used to investigate the haemolytic activities in culture supernatants of both methicillin-sensitive and methicillin-resistant Staph. aureus isolates cultured with graded subinhibitory concentrations of LicA. Alpha-toxin secretion was detected by immunoblot analysis. Moreover, quantitative RT-PCR was performed to assess the influence of LicA on the transcription of hla (the gene encoding alpha-toxin) and agr (accessory gene regulator). Growth in the presence of LicA markedly inhibited the mRNA levels of hla and agr in Staph. aureus, resulting in a reduction of alpha-toxin secretion and, thus, haemolytic activities.Conclusion:The secretion of alpha-toxin in Staph. aureus is decreased by LicA; this effect may be partially dependent upon inhibition of the Agr two-component system.Significance and Impact of the Study:The findings in our study may support the use of LicA as a lead compound in the design of more potent antibacterial agents that are based on the chalcone template.