Wang Xiaoling, Meng Shuo, Han Jingshi
School of Mechanical Engineering, University of Science and Technology, Beijing, P. R. China.
John A. Paulson School of Engineering and Applied Science, Harvard University, Cambridge, MA, 02138, USA.
J Microbiol. 2017 Aug;55(8):619-627. doi: 10.1007/s12275-017-7041-z. Epub 2017 Jul 4.
In this study, we explored Bacillus subtilis biofilm growth under various conditions such as the use of substrates with different stiffnesses and nutrient levels using a well-developed optical imaging technique to spatially and temporally track biofilm growth. We also developed a quantitative method to characterize B. subtilis biofilm morphologies under various growth conditions. To determine biofilm rim irregularities, we used the dimensionless P2A ratio, defined as P/4πA, where P is the perimeter and A is the area of the biofilm. To estimate biofilm thickness from transmission images, we developed a calibration procedure based on Beer- Lambert's law and cross sectioning. Furthermore, to determine the distributions of different B. subtilis cell phenotypes during biofilm growth, we used a triple-fluorescence-labeled B. subtilis strain that expressed motility, matrix production, and sporulation. Based on this work, we are able to tune biofilm growth by changing its growing environment.
在本研究中，我们利用成熟的光学成像技术，在空间和时间上追踪生物膜生长，探索了枯草芽孢杆菌在各种条件下的生物膜生长情况，这些条件包括使用具有不同硬度和营养水平的底物。我们还开发了一种定量方法来表征不同生长条件下枯草芽孢杆菌生物膜的形态。为了确定生物膜边缘的不规则性，我们使用了无量纲的P2A比率，定义为P/4πA，其中P是生物膜的周长，A是生物膜的面积。为了从透射图像估计生物膜厚度，我们基于比尔-朗伯定律和切片技术开发了一种校准程序。此外，为了确定生物膜生长过程中不同枯草芽孢杆菌细胞表型的分布，我们使用了一种表达运动性、基质产生和孢子形成的三重荧光标记枯草芽孢杆菌菌株。基于这项工作，我们能够通过改变其生长环境来调节生物膜的生长。
