Song Fangchao, Wang Hao, Sauer Karin, Ren Dacheng
Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, United States.
Syracuse Biomaterials Institute, Syracuse, NY, United States.
Front Microbiol. 2018 Feb 1;9:110. doi: 10.3389/fmicb.2018.00110. eCollection 2018.
Recently, we reported that the stiffness of poly(dimethylsiloxane) (PDMS) affects the attachment of , and the morphology and antibiotic susceptibility of attached cells. To further understand how responses to material stiffness during attachment, the wild-type PAO1 and several isogenic mutants were characterized for their attachment on soft and stiff PDMS. Compared to the wild-type strain, mutation of the gene abolished the differences in attachment, growth, and size of attached cells between soft and stiff PDMS surfaces. These defects were rescued by genetic complementation of . We also found that the wild-type PAO1 cells attached on soft (40:1) PDMS have higher level of intracellular cyclic dimeric guanosine monophosphate (c-di-GMP), a key regulator of biofilm formation, compared to those on stiff (5:1) PDMS surfaces. Consistently, the mutants of and , which have similar high-level c-di-GMP as the mutant, exhibited defects in response to PDMS stiffness during attachment. Collectively, the results from this study suggest that can sense the stiffness of substrate material during attachment and respond to such mechanical cues by adjusting c-di-GMP level and thus the following biofilm formation. Further understanding of the related genes and pathways will provide new insights into bacterial mechanosensing and help develop better antifouling materials.
最近，我们报道了聚二甲基硅氧烷（PDMS）的硬度会影响[具体细菌名称未给出]的附着，以及附着细胞的形态和抗生素敏感性。为了进一步了解[具体细菌名称未给出]在附着过程中如何响应材料硬度，对野生型PAO1和几个同基因突变体在柔软和坚硬的PDMS上的附着情况进行了表征。与野生型菌株相比，[具体基因名称未给出]基因的突变消除了柔软和坚硬的PDMS表面之间在附着、生长和附着细胞大小方面的差异。这些缺陷通过[具体基因名称未给出]的基因互补得以挽救。我们还发现，与附着在坚硬（5:1）PDMS表面的野生型PAO1细胞相比，附着在柔软（40:1）PDMS上的野生型PAO1细胞具有更高水平的细胞内环状二聚鸟苷单磷酸（c-di-GMP），这是生物膜形成的关键调节因子。一致地，[具体基因名称未给出]和[具体基因名称未给出]的突变体，其c-di-GMP水平与[具体基因名称未给出]突变体相似，在附着过程中对PDMS硬度的响应表现出缺陷。总的来说，这项研究的结果表明，[具体细菌名称未给出]在附着过程中能够感知底物材料的硬度，并通过调节c-di-GMP水平进而调节随后的生物膜形成来响应这种机械信号。对相关基因和途径的进一步了解将为细菌机械传感提供新的见解，并有助于开发更好的防污材料。
