Measuring the stiffness of bacterial cells from growth rates in hydrogels of tunable elasticity.
Measuring the stiffness of bacterial cells from growth rates in hydrogels of tunable elasticity.
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DOI：
10.1111/j.1365-2958.2012.08063.x
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发表时间：
2012-06
影响因子：
3.6
通讯作者：
Weibel DB
中科院分区：
文献类型：
--
作者：
Tuson HH;Auer GK;Renner LD;Hasebe M;Tropini C;Salick M;Crone WC;Gopinathan A;Huang KC;Weibel DB
虽然已知细菌细胞会受到渗透压差及其局部微环境的巨大作用力，但对生长中的细菌细胞的机械特性的定量测量是有限的。我们提供了一种实验方法和理论框架来测量活细菌的机械性能。我们将细菌包封在琼脂糖中，并设定硬度，测量单个细胞的生长速率，并将数据拟合到薄壳力学模型中，提取大肠杆菌（50-150 MPa）、枯草芽孢杆菌（100-200 MPa）和铜绿假单胞菌（100-200 MPa）的有效纵向杨氏模量。我们的数据提供了细胞壁刚度的估计值，类似于通过更劳动密集型的原子力显微镜技术获得的值。为了解决产生细胞力学特性变化的生理扰动，我们测试了a22诱导的MreB解聚对大肠杆菌硬度的影响。有效的纵向杨氏模量在短时间尺度上没有受到A22处理的显著影响，这支持了MreB与细胞壁之间的相互作用在与生长相同的时间尺度上持续存在的模型。因此，我们的技术能够快速确定基因型和生物化学的变化如何影响细菌包膜的机械特性。
Although bacterial cells are known to experience large forces from osmotic pressure differences and their local microenvironment, quantitative measurements of the mechanical properties of growing bacterial cells have been limited. We provide an experimental approach and theoretical framework for measuring the mechanical properties of live bacteria. We encapsulated bacteria in agarose with a user-defined stiffness, measured the growth rate of individual cells, and fit data to a thin-shell mechanical model to extract the effective longitudinal Young's modulus of the cell envelope of Escherichia coli (50–150 MPa), Bacillus subtilis (100–200 MPa), and Pseudomonas aeruginosa (100–200 MPa). Our data provide estimates of cell wall stiffness similar to values obtained via the more labor-intensive technique of atomic force microscopy. To address physiological perturbations that produce changes in cellular mechanical properties, we tested the effect of A22-induced MreB depolymerization on the stiffness of E. coli. The effective longitudinal Young's modulus was not significantly affected by A22 treatment at short time scales, supporting a model in which the interactions between MreB and the cell wall persist on the same time scale as growth. Our technique therefore enables the rapid determination of how changes in genotype and biochemistry affect the mechanical properties of the bacterial envelope.
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DOI：
10.2174/1568005014606116
发表时间：
2001-08-01
期刊：
Current Drug Targets - Infectious Disorders
影响因子：
--
作者：
Ha, S.;Gross, B.;Walker, S.
通讯作者：
Walker, S.
影响因子：
2.2
作者：
Eaton, Peter;Fernandes, Joao C.;Malcata, F. Xavier
通讯作者：
Malcata, F. Xavier
DOI：
10.1073/pnas.0805309105
发表时间：
2008-12-09
影响因子：
11.1
作者：
Huang, Kerwyn Casey;Mukhopadhyay, Ranjan;Wingreen, Ned S.
通讯作者：
Wingreen, Ned S.
DOI：
10.1073/pnas.0402638101
发表时间：
2004-06-08
影响因子：
11.1
作者：
Gitai, Z;Dye, N;Shapiro, L
通讯作者：
Shapiro, L
影响因子：
8.6
作者：
Boulbitch, A;Quinn, B;Pink, D
通讯作者：
Pink, D