Selective sweeps in growing microbial colonies.
Selective sweeps in growing microbial colonies.
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DOI：
10.1088/1478-3975/9/2/026008
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发表时间：
2012
期刊：
影响因子：
2
通讯作者：
Nelson DR
中科院分区：
文献类型：
--
作者：
Korolev KS;Müller MJ;Karahan N;Murray AW;Hallatschek O;Nelson DR
微生物的进化实验是研究突变和自然选择的有力工具。然而，这些实验通常限于试管或恒化器的良好混合环境。由于空间组织可以显着影响进化动力学，需要在空间结构化的环境中进行进化实验。培养皿的表面提供了这样的环境，但是更详细地了解培养皿上的微生物生长对于解释这样的实验是必要的。我们制定了一个简单的确定性反应扩散模型，成功地预测了两个竞争物种在殖民地扩张过程中所产生的空间格局。我们还推导出这些图案的形状分析，而不依赖于微观细节的模型。特别是，我们发现，两种微生物菌株的相对适合度可以从选择性扫描创建的对数螺旋来估计。该理论进行了测试与芽殖酵母酿酒酵母菌株，空间竞争与不同的初始条件和一系列的相对适合度。反应扩散模型还将生长速率和扩散常数等微观参数与宏观空间模式联系起来，并预测了液体培养物和培养皿中的适应度之间的关系，我们通过实验证实了这一点。因此，空间扇区模式为常用的液体培养适合性测定提供了替代适合性测定。
Evolutionary experiments with microbes are a powerful tool to study mutations and natural selection. These experiments, however, are often limited to the well-mixed environments of a test tube or a chemostat. Since spatial organization can significantly affect evolutionary dynamics, the need is growing for evolutionary experiments in spatially structured environments. The surface of a Petri dish provides such an environment, but a more detailed understanding of microbial growth on Petri dishes is necessary to interpret such experiments. We formulate a simple deterministic reaction-diffusion model, which successfully predicts the spatial patterns created by two competing species during colony expansion. We also derive the shape of these patterns analytically without relying on microscopic details of the model. In particular, we find that the relative fitness of two microbial strains can be estimated from the logarithmic spirals created by selective sweeps. The theory is tested with strains of the budding yeast Saccharomyces cerevisiae, for spatial competitions with different initial conditions and for a range of relative fitnesses. The reaction-diffusion model also connects the microscopic parameters like growth rates and diffusion constants with macroscopic spatial patterns and predicts the relationship between fitness in liquid cultures and on Petri dishes, which we confirmed experimentally. Spatial sector patterns therefore provide an alternative fitness assay to the commonly used liquid culture fitness assays.
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影响因子：
3.4
作者：
Nguyen, B;Upadhyaya, A;Brenner, MP
通讯作者：
Brenner, MP
影响因子：
8.8
作者：
Habets, Michelle G. J. L.;Rozen, Daniel E.;de Visser, J. Arjan G. M.
通讯作者：
de Visser, J. Arjan G. M.
影响因子：
2.9
作者：
Coberly, L. Caitlin;Wei, Wei;Krone, Stephen M.
通讯作者：
Krone, Stephen M.
DOI：
10.1073/pnas.0710150104
发表时间：
2007-12-11
影响因子：
11.1
作者：
Hallatschek, Oskar;Hersen, Pascal;Nelson, David R.
通讯作者：
Nelson, David R.
DOI：
10.1086/661897
发表时间：
2011-10
期刊：
The American naturalist
影响因子：
--
作者：
Korolev KS;Xavier JB;Nelson DR;Foster KR
通讯作者：
Foster KR