Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, College of Animal Science and Department of Food Quality and Safety, Jilin University, Changchun, China.
Appl Microbiol Biotechnol. 2015 Jan;99(1):359-73. doi: 10.1007/s00253-014-6076-x. Epub 2014 Sep 27.
Staphylococcus aureus is one of the most important pathogens in humans and animals. The formation of biofilm by S. aureus is considered an important mechanism of antimicrobial resistance. Therefore, finding effective drugs against the biofilm produced by S. aureus has been a high priority. Licochalcone A (LAA), a natural plant product, was reported to have antibacterial activities and showed good activity against all 21 tested strains of S. aureus biofilm and planktonic cells. To detect the possible molecular mechanism of LAA against S. aureus biofilm or planktonic cells, Affymetrix GeneChips were used to determine the global comparative transcription of S. aureus biofilm and planktonic cells triggered by treatment with sub-bactericidal and sub-inhibitory concentrations of LAA, respectively. LAA significantly altered (greater than a 2- or less than -2-fold change) the expression of 693 genes in planktonic cells and 817 genes in biofilm. The levels of genes encoding autolysis-associated proteins, cell wall proteins, pathogenic factors, protein synthesis genes, and enzymes involved in capsule synthesis were significantly altered in LAA-treated S. aureus. Furthermore, some differences observed in the microarray analysis were verified by real-time RT-PCR. To our knowledge, this is the first observation of phenotype and expression profiles of S. aureus biofilm and planktonic cells in response to LAA treatment.
金黄色葡萄球菌是人类和动物中最重要的病原体之一。金黄色葡萄球菌形成生物膜被认为是一种重要的抗微生物耐药机制。因此，寻找有效对抗金黄色葡萄球菌生物膜的药物一直是当务之急。甘草查尔酮 A（LAA）是一种天然植物产物，据报道具有抗菌活性，对 21 株金黄色葡萄球菌生物膜和浮游细胞均表现出良好的活性。为了检测 LAA 对金黄色葡萄球菌生物膜或浮游细胞的可能分子机制，分别使用 Affymetrix GeneChips 来确定亚杀菌和亚抑制浓度的 LAA 处理后金黄色葡萄球菌生物膜和浮游细胞的全局比较转录。LAA 显著改变了浮游细胞中 693 个基因和生物膜中 817 个基因的表达（大于 2 倍或小于 2 倍的变化）。LAA 处理的金黄色葡萄球菌中与自溶相关蛋白、细胞壁蛋白、致病因子、蛋白质合成基因和参与荚膜合成的酶编码的基因水平显著改变。此外，通过实时 RT-PCR 验证了微阵列分析中观察到的一些差异。据我们所知，这是首次观察到 LAA 处理对金黄色葡萄球菌生物膜和浮游细胞表型和表达谱的影响。
