Nilsson Martin, Givskov Michael, Twetman Svante, Tolker-Nielsen Tim
Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark.
Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore 637551, Singapore.
Microorganisms. 2019 Sep 3;7(9):310. doi: 10.3390/microorganisms7090310.
Screening of a mutant library indicated that mutants displayed a reduced biofilm-associated tolerance toward gentamicin. The biofilms formed by the mutant also displayed decreased tolerance towards linezolid and vancomycin compared to wild-type biofilms. On the contrary, the resistance of planktonic cells to gentamycin, linezolid, and vancomycin was more similar to wild-type levels. Investigations of biofilms grown in microtiter trays and on submerged glass slides showed that mutants formed roughly the same amount of biofilm as the wild type, indicating that the reduced antimicrobial tolerance of these mutants is not due to diminished biofilm formation. The gene product is known to be involved in the synthesis of precursors for cell wall components such as teichoic acids and membrane glycolipids. Accordingly, the mutant showed increased sensitivity to Congo Red, indicating that it has impaired cell wall integrity. A changed cell wall composition of the mutant may play a role in the increased sensitivity of biofilms toward antibiotics.
对一个突变体文库的筛选表明，突变体对庆大霉素表现出与生物膜相关的耐受性降低。与野生型生物膜相比，该突变体形成的生物膜对利奈唑胺和万古霉素的耐受性也降低。相反，浮游细胞对庆大霉素、利奈唑胺和万古霉素的抗性与野生型水平更相似。对在微量滴定板和浸没载玻片上生长的生物膜的研究表明，突变体形成的生物膜量与野生型大致相同，这表明这些突变体对抗菌药物耐受性降低并非由于生物膜形成减少。已知该基因产物参与细胞壁成分（如磷壁酸和膜糖脂）前体的合成。因此，该突变体对刚果红的敏感性增加，表明其细胞壁完整性受损。该突变体细胞壁组成的改变可能在其生物膜对抗生素敏感性增加中起作用。
