Department of Biomaterials Engineering, Institute of Bioscience & Biotechnology, Kangwon National University, Chuncheon, South Korea.
FEMS Microbiol Lett. 2011 Dec;325(2):180-8. doi: 10.1111/j.1574-6968.2011.02429.x. Epub 2011 Oct 17.
This study was designed to evaluate gene expression patterns of the planktonic and biofilm cells of Staphylococcus aureus and Salmonella Typhimurium in trypticase soy broth adjusted to pH 5.5 and pH 7.3. The planktonic and biofilm cells of multiple antibiotic-resistant S. aureus (S. aureus(R) ) and S. Typhimurium (S. Typhimurium(R) ) were more resistant to β-lactams than those of antibiotic-susceptible S. aureus (S. aureus(S) ) and S. Typhimurium (S. Typhimurium(S) ) at pH 5.5 and pH 7.3. The relative gene expression levels of norB, norC, and mdeA genes were increased by 7.0-, 4.7-, and 4.6-fold, respectively, in the biofilm cells of S. aureus(S) grown at pH 7.3, while norB, norC, mdeA, sec, seg, sei, sel, sem, sen, and seo genes were stable in the biofilm cells of S. aureus(R) . This study provides useful information for understanding gene expression patterns in the planktonic and biofilm cells of antibiotic-resistance pathogens exposed to acidic stress.
本研究旨在评估金黄色葡萄球菌和鼠伤寒沙门氏菌浮游细胞和生物膜细胞在调整至 pH 5.5 和 pH 7.3 的胰蛋白酶大豆肉汤中的基因表达模式。多药耐药金黄色葡萄球菌(金黄色葡萄球菌(R))和鼠伤寒沙门氏菌(鼠伤寒沙门氏菌(R))的浮游细胞和生物膜细胞对β-内酰胺类抗生素的耐药性强于 pH 5.5 和 pH 7.3 时的抗生素敏感金黄色葡萄球菌(金黄色葡萄球菌(S))和鼠伤寒沙门氏菌(鼠伤寒沙门氏菌(S))。在 pH 7.3 下生长的金黄色葡萄球菌(S)生物膜细胞中,norB、norC 和 mdeA 基因的相对基因表达水平分别增加了 7.0 倍、4.7 倍和 4.6 倍,而 norB、norC、mdeA、sec、seg、sei、sel、sem、sen 和 seo 基因在金黄色葡萄球菌(R)生物膜细胞中稳定。本研究为理解耐酸性应激的抗生素耐药性病原体浮游细胞和生物膜细胞中的基因表达模式提供了有用的信息。