Development of method for evaluating cell hardness and correlation between bacterial spore hardness and durability.
Development of method for evaluating cell hardness and correlation between bacterial spore hardness and durability.
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DOI：
10.1186/1477-3155-10-22
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发表时间：
2012-06-07
影响因子：
10.2
通讯作者：
Deuchi K
中科院分区：
文献类型：
--
作者：
Nakanishi K;Kogure A;Fujii T;Kokawa R;Deuchi K
尽管有用于进行单细胞操作的常规设备，但确定单细胞的硬度仍然很困难。在这里，我们将细胞视为线性弹性体，并应用杨氏模量（弹性模量），其定义为排斥力（应力）与所施加应变的比率。在这种新方法中，扫描探针显微镜（SPM）在“接触和推动”模式下使用悬臂进行操作，并将悬臂施加到细胞表面一定的距离（施加应变）。我们测定了以下细菌细胞的硬度：大肠杆菌、金黄色葡萄球菌、铜绿假单胞菌和五种芽孢杆菌。在对数期，这些菌株具有相似的杨氏模量，但芽孢杆菌属。孢子明显比相应的营养细胞坚硬。细菌孢子的硬度与耐热或紫外线 (UV) 耐受性之间存在正线性相关关系。使用这种技术，可以根据杨氏模量确定单个营养细菌细胞或孢子的硬度。作为这项技术的应用，我们证明了单个细菌孢子的硬度与耐热性和抗紫外线性成正比，这是物理耐久性的传统衡量标准。该技术可以快速、直接地测定孢子的耐久性，并为微生物学领域的物理特性评估提供了一种有价值的创新方法。
Despite the availability of conventional devices for making single-cell manipulations, determining the hardness of a single cell remains difficult. Here, we consider the cell to be a linear elastic body and apply Young’s modulus (modulus of elasticity), which is defined as the ratio of the repulsive force (stress) in response to the applied strain. In this new method, a scanning probe microscope (SPM) is operated with a cantilever in the “contact-and-push” mode, and the cantilever is applied to the cell surface over a set distance (applied strain). We determined the hardness of the following bacterial cells: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and five Bacillus spp. In log phase, these strains had a similar Young’s modulus, but Bacillus spp. spores were significantly harder than the corresponding vegetative cells. There was a positive, linear correlation between the hardness of bacterial spores and heat or ultraviolet (UV) resistance. Using this technique, the hardness of a single vegetative bacterial cell or spore could be determined based on Young’s modulus. As an application of this technique, we demonstrated that the hardness of individual bacterial spores was directly proportional to heat and UV resistance, which are the conventional measures of physical durability. This technique allows the rapid and direct determination of spore durability and provides a valuable and innovative method for the evaluation of physical properties in the field of microbiology.
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影响因子：
3.2
作者：
Paredes-Sabja, Daniel;Setlow, Barbara;Sarker, Mahfuzur R.
通讯作者：
Sarker, Mahfuzur R.
影响因子：
64.8
作者：
Sugimoto, Yoshiaki;Pou, Pablo;Custance, Oscar
通讯作者：
Custance, Oscar
DOI：
10.1073/pnas.0601744103
发表时间：
2006-04-18
影响因子：
11.1
作者：
Michel, JP;Ivanovska, IL;Schmidt, CF
通讯作者：
Schmidt, CF
影响因子：
4
作者：
Setlow, P.
通讯作者：
Setlow, P.